Arian Edalat spent the first half of his 22 years in desalination watching membranes foul, and the second half learning to talk back to them: Active Membranes, co-founded on a UCLA coating, makes a reverse-osmosis membrane electrically conductive, feeds it a few volts and lets the surface repel the salts that would crust onto it. In its first long pilot, in Yuma, Arizona, that meant run at 84% recovery with no antiscalant, about 92% with a second stage on the brine, and cleaning events cut from nine to three, by the company’s count. But the money is what caught my attention: Arian has raised about $3.2 million, grants included, and the $5 million round he is raising now is meant to be the last one before profitability. So, with ZwitterCo at close to $98 million for a membrane, I went into my Leviathan database to see whether the market agrees.

Why do reverse osmosis membranes foul, and what does it cost?

Every desalination plant is engineered around one enemy. Fouling, the organic layers that settle on a membrane, and scaling, minerals such as gypsum crystallising on its surface, cost an operator chemicals, energy, downtime and membranes: nine cleaning events in nine months on the Yuma plant Arian Edalat piloted on. And he calls it the tail that wags the dog.

Reverse osmosis, RO from here on, pushes salty water through a membrane at pressure so that only the water gets across, and the membrane has no say in what arrives (in Arian’s words it is a dumb plastic), so everything upstream of it exists to protect it. I made the same point in my desalination editorial last year: RO uses about ten times less energy than boiling seawater, but its membranes foul, scale and break like any industrial process. Well, the bill lands on the operator, because an hour of cleaning in 50°C heat is an hour a community goes without water. NALA Membranes attacks the same pain from the material side, with a polymer that survives chlorine.

How does an electrically conductive membrane stop scaling?

Active Membranes coats a standard polyamide RO membrane until its surface resistivity (the resistance across one square of surface, in ohms per square) drops from 10^7 to between 100 and 200, about five orders of magnitude. A low-voltage alternating signal, 4 volts at 1 hertz, then lets the charged surface repel charged ions before they nucleate, or seed a first crystal.

Now, polyamide is the thin active layer of nearly every RO membrane sold today, and it is an insulator, so nobody had bothered to plug one in. So I will spare you the physics (I did some a long time ago, and it did not end well), because Arian’s own summary lands it better: the coated sheet ends up, in his words, “infinitely more conducting to electrical current”. And once electrons move through the surface, the membrane can push away the calcium, sulfate and other charged species that would seed a crystal, and because you can read its performance as you vary voltage, waveform and frequency, it tells you when a water is beating it.

Inside the Yuma pilot: 75% to 92% recovery, nine cleanings to three

In Yuma, Arizona, a brackish-water plant ran at 75% recovery. Without chemistry, the active membranes ran the same water at 84%; with a second stage on the brine, Arian puts the whole plant at about 92%, his figure, not a multiplication. Cleaning events fell from nine to three in nine months, and lifecycle savings came out between 32% and 60%.

Recovery rate is the share of the feed water that leaves a desalination plant as fresh water, the rest leaving as brine, so a plant at 75% sends a quarter of what it pumped in back out as brine, and every point of recovery is money twice. (Yes, I checked the company report in my Leviathan database before repeating this.) And it places Active Membranes at TRL 6 to 7, TRL being the NASA scale from 1 to 9 for how baked a technology is, so a prototype proven in real conditions, with 20-gallon-per-minute field trials on produced water and brackish groundwater. So, pilot figures, as the company reports them, and not yet a commercial plant.

Can you run reverse osmosis without antiscalant?

The single “aha” in head-to-head pilots is the missing chemical: no antiscalant dosing, no chemical clarifier upstream, one or two dosing pumps fewer, on the same skid, vessels and pump. And a produced-water site Arian had treated with two-stage chemical clarification in 2018 ran again with none, at half the footprint and half the cost.

An antiscalant is a chemical dosed continuously upstream of an RO membrane to keep dissolved minerals from crystallising on it; it buys higher recovery, at the price of a chemical bill that never stops and a brine that is harder to dispose of. Now, my objection on air was about who books the saving, because the business model of an engineering consultant is copy-paste (he recovers the margin lost on his first three plants by reproducing the design), and Arian’s answer is that the consultant can keep copy-pasting the RO skid and simply stop copying the clarifier and two of the dosing pumps. Look, I dissected that adoption-chain problem in my newsletter last November, and it does not go away because the physics is good.

Can a $200 paint sprayer become a membrane factory?

The first conductive sheets came off a Home Depot drum coated with a handheld wall sprayer, a $200 rig built to enter the US Bureau of Reclamation’s “More Water, Less Concentrate” prize. Its successor, the Spitfire, sprays and heats the coating, was chosen after 20 spraying methods were screened, and now coats sheets for standard 4-inch and 8-inch elements.

The method came out of David Jassby’s laboratory at UCLA, and in January 2024 the university’s newsroom listed Jassby and Eric Hoek among the company’s co-founders. Getting from a lab bench to a spiral-wound element, the rolled membrane cartridge that slides into a pressure vessel, usually eats a membrane start-up’s first tens of millions, because the industry’s answer is a big, chunky coating line. Well, Arian says he did not have that money, so he had to be creative, and the Spitfire is what creative looked like (the name is affectionate, the machine less so). And by November 2025, Aquatech reported the first standard 8040 modules, eight inches by forty, and a seawater pilot lined up in Israel.

Franchising membrane production: KFC for membranes

Now, two things keep RO membranes in a handful of hands, the five or so producers I counted out with Arian on air, arguably three big ones: the capital a coating line costs and its concentration in a few mega-sites. So Active Membranes’ answer is a “mother” facility in California and partner-run coating and rolling lines in their own markets.

So the pitch to a partner in Malta or the Gulf is that the Spitfire comes to you, you coat and roll locally, and you own a product your competitors cannot buy. Now, an OEM, the company that builds the RO skid, then gets to choose between selling one plant a year at $1 million or ten plants at $500,000, because a plant without a chemical clarifier and with fewer dosing pumps fits budgets and sites that never penciled out. And that is the opposite of the path ZwitterCo took, which I raised on air: raise tens of millions, build the plant, own the capacity. Both can be right, but the second is the one investors are trained to fund.

Seedstrapping: grants first, one seed, then stretch

Seedstrapping is the pattern I named the week this episode aired: bootstrap on grants and non-dilutive money to the first paying customers, take one modest seed, then stretch it toward profitability. Active Membranes has done the first two steps, about $3.2 million in total, and the $5 million round it is raising now is meant to be the stretch.

Non-dilutive funding is money a company receives without giving up shares: grants, government research contracts such as the US Small Business Innovation Research awards, or profits from a sister business, and Arian used all of them, the sister business being Pacifica Water Solutions, the consultancy he co-founded in 2019, which reinvested into the venture. And he is not alone on this microphone: Swapnil Shrivastav of Uravu Labs told me too much cash makes you solve problems by throwing money, and Fajer Mushtaq of Oxyle took a technology from lab to full-scale product on $3 million of equity and $6 million of non-dilutive money. But the other side of the ledger is SOURCE Global, whose collapse I took apart in June.

Why do water VCs want founders to raise less?

Peter Yolles, founder and managing partner of Echo River Capital, which my Leviathan database has in 23 water rounds across 18 companies, says he looks for a long runway of technology development before founders raise dilutive capital. When has a VC ever told anyone to take less of their money? Well, in water, they practically beg you to.

I spent two weeks of evenings on the newsletter that named seedstrapping, because I am fun at parties, and the numbers held: Correlation Ventures’ analysis of 21,000-plus deals, which I walked through in August 2025, has 65% of venture investments failing to return their capital and 4% returning ten times. And water is harsher still, because you need paying customers before the risky VCs return your call, so the founder who arrives with proof instead of projections has already done the investor’s de-risking for free (and yes, Peter backed both Active Membranes and Uravu Labs). So his line, below, should be taught in water entrepreneurship schools, if those existed.

Are water-tech checks really getting smaller?

In August 2025 I counted about $600 million into water tech, more checks than 2024 and about 10% smaller. The full year in my Leviathan database deepened it: with the largest round of each year removed, 178 rounds for $977 million in 2025 against 166 for $1.14 billion in 2024, so 7% more rounds and a 20% smaller average check.

I keep every water funding round I can document in Leviathan, and the largest round of each year distorts everything: Lilac Solutions’ $145 million in 2024, Tidal Vision’s $140 million in 2025. So take those two out, as I did on the podcast, and the average check falls from $6.9 million to $5.5 million.

But the average is not the number that matters to a founder. The median, the check right in the middle of the pile, went from $3.2 million in 2024 to $2.2 million in 2025, a third smaller, so more companies got funded and the typical one got less, which is the market voting for something like what Arian is doing.

How does $3.2 million compare with what membrane peers raised?

Active Membranes’ $2.33 million seed is a normal seed: the median seed round in my database was $2.2 million in 2024 and $2.0 million in 2025. But ZwitterCo raised $97.7 million across four rounds, NALA Membranes $19.75 million across six, Evove $12.95 million, Aqua Membranes $7 million, and Active Membranes stands at $3.24 million across two entries.

The difference is in what comes after the seed, and I ran the same query for every membrane company that has sat on this microphone, so the figure below carries the whole list, Membrion included at $43 million. Now, the two cases worth walking are the poles: ZwitterCo raised thirty times what Active Membranes did, most of it in one $58.4 million round in July 2024, to build capacity, while NALA, whose chlorine-tolerant polymer I wrote up in July, sits at six times and is still adding rounds in 2026. Active Membranes’ seed closed the same month as ZwitterCo’s big round, led by Natural Ventures with Echo River Capital and Pacifica Water Solutions, for $2.3 million per PR Newswire, 10 July 2024.

Can a $5 million last round still return 10x?

My objection on air was Echo River’s own thesis: Peter Yolles believes 10x, even 100x, is possible in water, and 10x in six to eight years means hypergrowth, so machines and footprint paid upfront, franchise or not. His answer: low capital makes the mistakes smaller and the path nimbler, and 2030 ends in profitability or an exit.

Let’s walk the arithmetic, which is not investment advice. A $5 million last round caps the total raised at roughly $8 million, not all equity since the first $3.2 million mixes in grants, so a 10x on the shares sold needs an exit well north of $80 million, how far north depending on the investors’ share. In water membranes that means a strategic acquisition, not an IPO, and Arian says so (“a good exit would be nice at some point”) in a market of five or so RO membrane producers keener, as I put it to him on air, to partner on outside tech than to invent it. So he sits on the seedstrapper end of my newsletter’s barbell.

What 2026 is testing: XPRIZE semifinals, Israel, and the home KFC

Active Membranes now offers its first standard 8-inch by 40-inch modules and has a seawater pilot lined up in Israel, both reported by Aquatech in November 2025, and on 12 May 2026 XPRIZE named it a semifinalist in both tracks of its $119 million Water Scarcity competition, one of 37 teams, with finalists due in 2027 and winners in 2028.

Now, Track A tests whole desalination systems, about 1,000 litres a day over two weeks, and Track B tests new materials at laboratory scale, so a company in both is claiming to be a system and a material at once, which is the franchise argument in prize form. Aqua Membranes is in the same semifinal, so the spacer route and the conductive route will be measured side by side. And Arian’s own list for the next twelve months was shorter: build the home KFC in California, make it replicable, and cultivate the partners in Israel, the Mediterranean and the Middle East, “wars and things permitting”. He had a line about the industry that I will let him say himself.

Frequently asked questions

What is membrane fouling?

Membrane fouling is the build-up of organic matter, biofilm and particles on the surface of a reverse-osmosis membrane, which raises the pressure the plant needs and lowers its output. Every part of a desalination plant upstream of the membrane, from pretreatment to the recovery it runs at, is designed to limit it.

What is the difference between scaling and fouling of membranes?

Fouling is the deposit of organic, biological or particulate layers on the membrane. Scaling is dissolved minerals, such as calcium sulfate (gypsum) or calcium carbonate, crystallising on it once their concentration passes what the brine can hold. Active Membranes’ electrical control targets the charged species behind scaling and biofouling.

How do you prevent membrane fouling?

Conventionally with pretreatment, antiscalant dosing, pH control and periodic cleaning-in-place. Active Membranes’ electrically conductive coating lets the membrane repel charged foulants at its own surface, which is how the Yuma pilot ran without antiscalant and with three cleaning events in nine months instead of nine.

Is membrane fouling reversible?

Partly: cleaning-in-place removes the reversible layers, but every cleaning means downtime, chemicals and wear, and repeated cleanings shorten a membrane’s life. That is why cutting nine cleaning events to three in the Yuma pilot is a lifecycle-cost number rather than a convenience.

What is the biggest problem with desalination?

In Arian Edalat’s operator view, scaling and fouling: they drive the chemicals, the footprint and the complexity that keep desalination uneconomic below communities of roughly 5,000 to 10,000 people, which is where most of the unserved demand sits.

What is seedstrapping?

Seedstrapping is my term for bootstrapping on grants and non-dilutive money until the first paying customers, taking one modest seed round, then stretching it toward profitability. Active Membranes, with about $3.2 million raised and a $5 million round planned as its last, and Uravu Labs are the worked examples.

Who invested in Active Membranes?

A seed round closed in July 2024, led by Natural Ventures with Echo River Capital and Pacifica Water Solutions, for about $2.3 million, plus a 2025-tagged extension of about $0.9 million in my Leviathan database. The total of about $3.2 million that Arian quotes includes grants and prize money.

What is the XPRIZE Water Scarcity competition?

A $119 million competition backed by the Mohamed bin Zayed Water Initiative to make seawater desalination reliable, sustainable and affordable. On 12 May 2026 it named 37 semifinalists, 20 in Track A (systems) and 17 in Track B (materials); Active Membranes is in both. Finalists come in 2027 and winners in 2028.

Where this goes next

So if the $5 million round really is the last one, 2030 is the date Arian set himself, and the XPRIZE finals in 2028 will come first, which means somewhere between the two we will learn whether a membrane company can grow on a franchise of $200-rig descendants. The full hour with Arian is in the player above, and the seedstrapping playbook is in my newsletter if you want it before your next board meeting.

Sources

1. (don’t) Waste Water podcast, S13E7, “This $200 Hack Makes Desalination 50% Cheaper”, Arian Edalat, published 20 August 2025. https://www.youtube.com/watch?v=w8GH1tG4E1s
2. (don’t) Waste Water podcast, S12E14, “How Echo River Capital Sees 10x Water Returns as… Too Conservative!”, Peter Yolles, published 3 April 2025. https://www.youtube.com/watch?v=sayph9at-kY
3. Antoine Walter, “Why Elon Musk’s Desalination Vision is Failing”, solo editorial, 16 June 2025. https://www.youtube.com/watch?v=RLnCo3MMcSw (retrieved 2026-09-05)
4. Antoine Walter, “The ‘Seed-Strapping’ Era”, (don’t) Waste Water newsletter, 19 August 2025 (citing Correlation Ventures’ analysis of 21,000+ deals). https://www.linkedin.com/pulse/seed-strapping-era-antoine-walter-wkc2e/ (retrieved 2026-09-05)
5. PR Newswire, “Active Membranes Receives Initial Round of Seed Funding to Accelerate Development of Award-winning Desalination Technology”, 10 July 2024. https://www.prnewswire.com/news-releases/active-membranes-receives-initial-round-of-seed-funding-to-accelerate-development-of-award-winning-desalination-technology-302191370.html (retrieved 2026-09-05)
6. Natural Ventures, “Natural Ventures Invests in Active Membranes”, Abu Dhabi, 10 July 2024. https://natural.ventures/natural-ventures-invests-in-active-membranes/ (retrieved 2026-09-05)
7. UCLA Newsroom, “The future of fresh water is bright”, 31 January 2024. https://newsroom.ucla.edu/stories/active-membranes-water-desalination-magnify-incubator (retrieved 2026-09-05)
8. Aquatech, “Electrically charged membranes scale smarter”, 4 November 2025. https://www.aquatechtrade.com/water-stories/desalination/8040-smart-membranes-modules-breakthrough (retrieved 2026-09-05)
9. XPRIZE Foundation, “XPRIZE announces semifinalist teams advancing in $119M competition to transform seawater desalination”, 12 May 2026. https://www.xprize.org/news/semifinalists-announced-xprize-water-scarcity (retrieved 2026-09-05)
10. Water Online, “Active Membranes Advances To XPRIZE Water Scarcity Semifinals In Both Track A And Track B”, May 2026. https://www.wateronline.com/doc/active-membranes-advances-to-xprize-water-scarcity-semifinals-in-both-track-a-and-track-b-0001 (retrieved 2026-09-05)
11. Leviathan, Antoine Walter’s water funding database: funding rounds 2022 to 2026 (rounds with disclosed amounts; the single largest round of 2024 and 2025 excluded where stated), membrane-company totals, Echo River Capital’s participations (23 rounds, 18 companies), and the Active Membranes company report (TRL 6 to 7). Verified 2026-09-05.

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Reverse osmosis has run on essentially the same membrane for more than forty years, and it isn’t because nobody built a better one. Nala Membranes did. It’s a sulfonated polysulfone film that shrugs off chlorine where today’s polyamide membranes come apart, and that one property kills the biofouling that quietly eats about a quarter of a desalination plant’s operating cost. A major membrane manufacturer’s engineers looked at the chemistry, liked it, and their business side said no. So the question I actually wanted to answer isn’t whether the technology works, because it does. It’s whether a company that has raised $15.15 million, roughly a sixth of what ZwitterCo banked, can get a genuinely new material adopted in a market with three or four serious players that hasn’t changed its core material in two generations.

And I’m going somewhere with this, because the honest answer runs through the least glamorous corner of the water business and past at least one fresh grave.

What did Nala Membranes actually invent?

Nala Membranes is a North Carolina startup built on polymer-chemistry work from Virginia Tech and the University of Texas at Austin, co-founded by CEO Sue Mecham and Dr. Judy Riffle, and what it has made is the first new reverse osmosis membrane material in over forty years: a sulfonated polysulfone thin film composite.

Let me unpack that, because “thin film composite” (TFC) is doing a lot of work. Every modern RO membrane is a sandwich, and the slice that actually rejects the salt is a wafer-thin polymer layer laid on top of a support. Since the late 1970s that layer has been a polyamide, and polyamide has two well-known weaknesses: its surface is rough, so gunk sticks to it, and chlorine tears it apart, so you can’t use the cheapest, most obvious tool in water treatment to keep it clean. Before polyamide, the industry ran on cellulose acetate, which was smooth and could tolerate a bit of chlorine, but it lost the flux-and-rejection race and got displaced. Nala’s pitch is that it brought both of those old virtues back, with a new material and a new way of making it.

The smooth surface is the part chemists get excited about, because it comes from the manufacturing process, not from a coating you add on afterward. Nala makes its polymer first and then lays it down, where polyamide is grown in place on the membrane in a reaction that leaves behind a rough finish and a couple of nasty waste streams. Same trick the cellulose acetate people had, brought forward to a modern high-performance film.

The chlorine advantage, and the 24% it targets

Here’s the money question, because a chemistry curiosity only becomes an investable company when it changes a number on an operator’s spreadsheet, and for RO that number is biofouling. Biofouling is just bacteria setting up house on the membrane, and the standard, boring, cheap way to stop bacteria in water is chlorine. Polyamide can’t take it, so operators fight fouling with pre-treatment, downtime, and expensive cleaning cycles instead. Nala can take it, down at drinking-water doses to keep bugs from growing, and all the way up to 10,000 ppm of hypochlorite when a membrane is genuinely filthy.

There’s an old rule of thumb in this industry that if you’re not at least 20% better than the incumbent, you don’t get a seat at the table. Sue’s answer clears that bar, and she is careful to source it rather than round it up:

That’s an operating-cost story, which matters, because in most industrial water deals the argument long ago stopped being about the sticker price of the membrane and became about what it costs you to run the thing over its life. A membrane you can chlorine-clean instead of babysit is worth more every single year, not just on day one.

Why did the membrane giants pass on it?

This is the part that gives the episode its title, and it’s more instructive than the usual founder war story. Around 2010 and 2011, before Nala even existed, the underlying sulfonated polysulfone chemistry landed on the desk of one of the big membrane manufacturers. Their technical people ran tests and liked what they saw.

Now, my instinct when I hear “the giant turned it down” is to reach for the hall of fame of corporate blindness, and the episode does exactly that: Kodak sitting on the digital camera its own engineer built, Blockbuster waving Netflix through, Xerox letting personal computing walk out the door. The trouble is that this is survivor bias dressed up as destiny. Internet Explorer held nearly 96% of the browser market in the early 2000s while being nobody’s favorite browser. Betamax was better than VHS and lost anyway. We still type on QWERTY keyboards that were designed to slow us down. Incumbency is a moat, not an accident, and the academic read is that you need to reach somewhere between 15% and 30% market penetration before adoption becomes self-sustaining. Sue puts the same wall in plainer terms: on the membrane side, she says, people can’t even fathom what you mean by a new membrane, because it’s been so long since they had one. I’ve argued this at length in a newsletter on why your water tech is probably not as disruptive as your pitch deck claims, and if that debate is your kind of fun, my newsletter is where I keep having it.

Has anyone ever actually disrupted water tech?

Yes, but you can almost count the clean examples on one hand, and every one of them took a decade or three. These are the cases I keep reaching for on the show. Trojan started in 1977 as three people in Canada betting that ultraviolet light could replace chlorine for disinfection, and most of the industry laughed until UV became mainstream municipal practice in the 2000s. The pressure exchanger, the device that recovers up to 60% of the energy in a desalination plant, arrived in 1992 and didn’t become standard until the mid-2010s, by which point something like 70 million people were drinking water that had passed through one. And the canonical case is Andrew Benedek pushing the membrane bioreactor through the 1980s and 1990s while everyone told him membranes had no place in wastewater, right up until GE bought Zenon in 2006 and the idea became obvious.

So the material working is the easy part. The pattern in this sector is that a better mousetrap wins a niche first and the mainstream last, if ever. Even today, polymer membranes hold about 93% of the market against roughly 7% for ceramics, a 2025 Global Water Intelligence split I chewed over in my newsletter, and that gap has barely moved despite ceramics being genuinely excellent. Membranes, it turns out, don’t much like a winner-take-all story.

How does Nala’s $15 million stack up against the field?

This is where I get to plug in my own numbers, because I keep a section of my Leviathan database on exactly this cohort, the startups trying to move the membrane itself, and laid side by side they tell a story the pitch decks don’t.

Look at what most of that money is actually buying. ZwitterCo, which has raised close to six times what Nala has, puts a clever zwitterionic layer on top of a polyamide. Aqua Membranes, whose 3D-printed spacers I covered with Craig Beckman, improves the plumbing around the membrane. Evove, which I looked at through its lithium work, coats and prints. Nearly the whole field is innovating around the polyamide rather than replacing it, which is the rational thing to do, because replacing the material is the hardest possible version of this game. The one team that took a swing as deep as Nala’s, Aquaporin, built biomimetic membranes out of actual water-channel proteins, raised nearly $25 million doing it, and is now dead. That’s the company Nala keeps, and it’s worth sitting with before you get too excited about a founder claiming to have out-chemistried an entire industry on $15 million.

Can a bootstrapped startup out-patient the oligopoly?

I think the interesting answer is that Nala isn’t trying to beat the giants at all, and that’s precisely why it might work. Run it through the framework I use for this: a water tech can be disruptive on four fronts, creating a market, improving performance, cutting costs, or improving the user experience, and the earlier you are, the fewer of those you’re allowed to touch at once. Nala touches exactly two. It improves performance, by handling organics and chlorine that choke polyamide, and it cuts costs, by that 24%. Two, which is the ceiling I’d give a company this young. It is not also trying to invent a new market or reinvent how plants are operated, and that discipline shows up in the fundraising.

The go-to-market matches the money. Nala is starting in industrial wastewater, the semiconductor, textile, and mining streams that are loaded with the organics polyamide hates, where a customer feels the pain sharply enough to try something new, and where you don’t need to dislodge a giant to win the job. Manufacturing is deliberately asset-light: Nala makes its own polymer, coats a sourced substrate, and hands the sheet to a contractor to roll into modules, with, as Sue points out, no waste streams to dispose of at the end. It’s a company built to survive the twenty-year adoption clock rather than to sprint at it. There’s an exit shimmering somewhere out there too, and I’ll admit I floated the idea on the show that a private-equity-owned membrane major might one day want Nala as the premium “sparkle” on a commodity product, though that one is my speculation, not a plan on anyone’s desk.

Frequently asked questions

What is Nala Membranes?

A North Carolina startup, co-founded by CEO Sue Mecham and Dr. Judy Riffle, that has developed the first new reverse osmosis membrane material in over 40 years, a sulfonated polysulfone thin film composite.

What is a sulfonated polysulfone membrane?

A reverse osmosis membrane whose salt-rejecting layer is made from sulfonated polysulfone rather than the industry-standard polyamide. It has a smoother, more chlorine-tolerant surface, which reduces biofouling and allows aggressive chlorine cleaning.

Is Nala’s membrane really chlorine-tolerant?

Yes. Nala reports tolerance from drinking-water-level doses up to 10,000 ppm of sodium hypochlorite for cleaning, where standard polyamide membranes degrade on contact with chlorine.

How much has Nala Membranes raised?

About $15.15 million across five disclosed rounds, according to the Leviathan funding database, with a further roughly $5 million priced round open at the time of the interview.

How is Nala different from ZwitterCo or Aqua Membranes?

ZwitterCo coats a zwitterionic layer onto polyamide and Aqua Membranes prints spacers around existing membranes; both improve the incumbent. Nala replaces the separating material itself.

The one thing I’d watch

If you want to know whether this is the rare water-tech disruption that sticks, don’t watch the chemistry, which already works, and don’t watch the funding headline. Watch for two things: real, paid industrial-wastewater installations that survive a full cleaning season, and a strategic lead investor writing the check that says a serious player wants this material to exist. Get those, and the twenty-year clock starts running in Nala’s favor. As Sue puts it, the whole point is to make reverse osmosis cheaper and simpler so it can do what it’s supposed to do, and that’s a fight worth losing sleep over. The full conversation, chlorine chemistry and all, is the episode.

Related: the other route to a membrane that stops fouling: make it electrically conductive

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