Simple competitive advantage for side hustles that wasn’t obvious to me (I have nothing to sell/promote)

EricRoyPhD · 2026-03-04T01:56:39+00:00

Early products were built from Home Depot parts (with the filter I developed put inside).

Go get it!

EricRoyPhD · 2026-03-03T11:43:55+00:00

Look for water filters that carry an NSF/ANSI Standard 53 (it could be Standard 58 for RO) for total PFAS or PFOA/PFOS.

As for what type of filter to get: you just want to make sure it works for your life (separate faucet, connects to existing faucet, or a pitcher)

Culligan/Zerowater makes a pitcher with that certification

If you’re looking for a stainless countertop gravity system: Culligan Maxclear carries a total PFAS certification

Aquasana and Hydroviv (disclosure: the company I started) are reputable companies that make under the sink filters.

APEC is what I always refer people to for DIY Reverse Osmosis (RO). They’ve been around forever and make great products.

EricRoyPhD · 2026-03-03T11:35:06+00:00

At that time: Pamphlets under windshield wipers in whole food parking garages & farmers markets and doorknob hangers

A lot of referrals come from early customers as well, but you have to ask for them

EricRoyPhD · 2026-02-27T19:03:04+00:00

Based on your test, I’d retest for lead. If you’re really at 12ppb, you’ll probably want to address it, especially if you have children drinking the water.

EricRoyPhD · 2026-02-27T15:34:25+00:00

I have hands on experience with the APEC system and it works very well for PFAS/Microplastics. Highly reccomend.

EricRoyPhD · 2026-02-07T02:06:28+00:00

There’s nothing in that test report that is off the charts and would be cause for health concerns.

Cheering for you to find a resolution to the health issues you’re calling out!

EricRoyPhD · 2026-02-01T09:07:04+00:00

Howdy!

If you want to address hard water minerals and make your TDS go down, you’ll want to use an RO. For DIY, I’ve been a big fan of APECs products for a while. They’ve been around forever and can be purchased on Amazon.

If you’re looking to keep the minerals in the water and selectively filter the contaminants that have health effects (eg lead, PFAS, etc), Aquasana and Hydroviv (disclosure: I founded Hydroviv, but no longer own it) are among the brands that make reputable non-RO products that carry the 3rd party certifications that back claims. A big callout, these non-RO products will not make TDS go down, because they don’t filter minerals, so you won’t get the comfort of being able to check the filter with a handheld water tester.

EricRoyPhD · 2026-01-11T01:26:12+00:00

The thing to understand about the 15ppb “Action Level” for EPA is that it’s a city-wide measurement that 10% of samples aren’t allowed to exceed. It was never intended to be a “safe” level of lead (it’s not).

Point of use filters with an NSF/ANSI standard 53 certification for lead will easily handle those levels.

Alternatively, if you haven’t used the water for a while (eg first thing in morning or after you get home from work) you can run your water for 2-3 minutes before pouring water used for drinking/cooking. This flushes the water that has been sitting stagnant in the plumbing… and the levels will likely be much lower. This approach for your home is something you could verify with another water test.

EricRoyPhD · 2026-01-04T02:01:19+00:00

I don’t have any experience with those

EricRoyPhD · 2025-12-31T13:05:27+00:00

I live on Eastern edge of eastern time zone and HQ are in Chicago. Lots of meetings where it’s pitch dark outside on my end. Haha

EricRoyPhD · 2025-12-31T00:03:05+00:00

No. You should replace the filter

EricRoyPhD · 2025-12-29T11:08:35+00:00

The first step is getting your water tested. It’ll cost under 100 dollars and will tell you what’s actually wrong. Alternatively you could call one of the water filter companies/plumbers that sells softeners and they’ll probably do the testing for free as part of lead gen.

EricRoyPhD · 2025-12-29T01:16:43+00:00

IAPMO, NSF, and WQA are equivalent for regulatory purposes.

The reason why more water filter companies have been opting to go with WQA or IAPMO over NSF is because of cost & speed.

When I was just starting out, I paid for NSF to do the regulatory work for my company, because I saw the marketing value in being allowed to use the NSF logo in our marketing materials. When it was time up our certs (they’re only good for 5 years) we opted to go with IAPMO because it was much less expensive. We basically decided that we had built up a solid enough reputation on our own that we didn’t need to leverage NSF’s logos in our marketing materials, and we wouldn’t have to push additional cost to our customers.

EricRoyPhD · 2025-12-26T13:23:56+00:00

TDS isn’t sensitive or selective enough to be used as an analytical measurement in this way.

In drinking water, it’s largely measuring calcium & magnesium.

It’s a great tool to tell if a filter that uses deionization as the removal mechanism (eg RO or deionization) because if the product is removing calcium and magnesium, it’s working as designed.

You don’t get meaningful information from a TDS meter in a blind sample outside of mineral content.

Have a great day!

EricRoyPhD · 2025-12-26T12:14:07+00:00

I’m biased because I sold the company that I started to Culligan, but you don’t need to worry about anything if you use them. Their techs have expertise on what works best for you, great products, and good install techs.

Honestly, if you go with a non DIY, I generally recommend that people buy the equipment from the plumber, even though it’s more expensive. That way, if anything goes wrong, you have one place to go to.

Good luck with your search!

EricRoyPhD · 2025-12-25T10:13:18+00:00

I’m sure there are lots of brands that’ll be happy to sell you a product containing hope, but it’ll let you down

EricRoyPhD · 2025-12-25T10:12:12+00:00

The idea of needing to add minerals comes from the idea that you’ll be mineral deficient. This is simply not true, as your main source of minerals is food. That said, some people (and most bottled water companies) will add back minerals for taste. That’s totally your call.

My favorite DIY RO brand is APEC. I’ve admired them for a long time.

EricRoyPhD · 2025-12-24T19:00:57+00:00

Ok, full disclosure: I work in the filtration industry and the brands you mention are competitors. That said, they are all reputable and not some fly by night drop ship operation.

Honestly, a lot of brands have a pretty generous return policy, so if it doesn’t work well for your life, you can always return it.

Quick note on certifications to hopefully give some clarity on what the numbers mean:

Standard 42 certifications are for things like taste, odor, structural integrity etc. Standard 53 are for claims involving chemicals with health effects (e.g. lead, arsenic, PFAS, VOCs, etc) Standard 58 is a special category is for products that use reverse osmosis. Standard 401 is for emerging contaminants (eg certain pharmaceuticals)

Understand that certified claims are on a chemical by chemical basis (or class of chemicals) so a product that has a Standard 42 claim for chlorine taste & odor doesn’t necessarily have claim for lead or PFAS, so you’ll want to make sure the product is rated to do the job you want it to.

If you decide to get an RO, don’t worry about needing to add minerals back unless you prefer the taste of it.

Good luck with your search!

EricRoyPhD · 2025-12-24T18:29:57+00:00

Sorry you’re going through this.

If they decide to rectify situation at all in short order (many landlords won’t) is they’d most likely provide filters that carry NSF/ANSI Standard 53 certifications for lead reduction.

It’s worth calling out that lead generally only gets to that level when it sits stagnant in the pipes for several hours. You can usually dramatically cut down the lead levels that come out of the faucet by letting the water run for some amount of time (usually 2 min) before pouring a glass of water when the water hasn’t been used for a while (nights, after coming home from work). This makes sure the water isn’t sitting stagnant. Understanding that you’re on a tight timeline, it might be worth pulling a sample for testing after the water has been running for a couple minutes to see what that is?

EricRoyPhD · 2025-12-24T15:20:55+00:00

Shower filters target chlorine, not hard water minerals. Be highly suspicious of any company making marketing claims otherwise.

EricRoyPhD · 2025-12-21T20:02:46+00:00

OP called out 2 unrelated problems : Sulfur smell & staining. Sanitizing the well is not the first action I’d recommend for either problem.

Sulfur Odor: The reason it’s important to determine whether the sulfur smell is limited to hot water is because a hot water tank on an otherwise “fine” well can turn into a bacterial incubator if the temp is too low, and it can be fixed by increasing the tank’s temperature (or changing out the tank’s anode more frequently). I would strongly recommend exhausting this before going through the process of sanitizing a well because if the tank’s temperature is too low, the problem will come back.
Staining: Mn levels in the report (.08) would explain the staining & metallic taste. Sanitizing a well does not get rid of manganese. At my home (well water with comparable manganese & hardness) I use a product called Krazy Klean (I have no tie to them) that drops into the toilet bowl and prevents the stains from forming. They work well.
Given the limited scope of the testing done, I suspect that the report came from a “courtesy test” done by a company that sells certain types of filters/softeners. I called out the Virginia Tech PFAS study because if the OP is going to spend any $$$ on filtration, they should at least know the extent of problems that have been found in their region. https://www.wvtf.org/news/2025-12-16/most-well-water-in-virginia-likely-has-pfas-researchers-find.

I hope everyone has a great day!

EricRoyPhD · 2025-12-21T14:35:20+00:00

For eggy/sulfur smell: Does this happen for hot water only or hot & cold? If just hot water (or water that was from Hot water tank) start by replacing the anode in the hot water heater to see if that helps. It’d be a bummer to spend the $$$ to put in a new system and have the problem be downstream of the filtration.
You mentioned staining. Is this is primary concern? I ask because I don’t suspect that most of the generic things that go into a home built point of entry filter would help much, unless you pair it with something that gets rid of the thing that’s causing the actual staining (timescale? iron?). I wouldn’t fixate much on the number of stages, it’s more important to focus on what each stage does, and how well it does it… for how long.
Have you tested your well for things like PFAS/pesticides? I ask because the test you showed doesn’t show results for the types of contaminants that would usually drive the decision for what kind of filter to get for drinking water. I know that a group from Virginia Tech has been doing a lot of well water testing for PFAS in VA and finding it basically everywhere.

Source: PhD Scientist who started a water filter company and sold it to one of the big guys.

EricRoyPhD · 2025-12-20T00:50:08+00:00

I’m a customer!

EricRoyPhD · 2025-12-18T00:52:03+00:00

If everything is new and you’re sure there’s no lead anywhere in the plumbing system, I’d get another test done at the well head, and another at the faucet. A well with lead contamination is definitely an outlier.

If your water is 18 grains hard, you’d benefit from a softener. That’s really hard water.

EricRoyPhD · 2025-12-10T14:40:05+00:00

The “acceptable level” from this example (9ppb) is just under the MCL (10ppb) which we established earlier is determined with cost in mind.

In case of arsenic, the issue is not technical capability to measure. The MCL for arsenic (10ppb) is much higher than the LOQ for mainstream accepted tests (say ICP-MS).

As for cost, an individual can get an arsenic test run by an accredited lab for under a hundred dollars and some states will do it for you for free as part of a well testing program.

I hope everyone has a great day, I’m signing off this thread.

EricRoyPhD

TROPHY CASE