Generic Purigen = Cloudy Water (I think)

TMF89 · Feb 10, 2025

Hey guys, I bought a two pack of knock-off Purigen on Amazon. I know the risks of using off-brand stuff, but it has a ton of great reviews, with loads of people specifically mentioning how it works just as well as the original, at a much better price. I rinsed off both packs, and added one to my 75 gallon cichlid tank, with no issues, and the water definitely seems crystal clear. Much to my surprise, I woke up the morning after adding it to my 40 gallon reef tank to find a bunch of cloudy water. It's off-white, and murky enough that I can barely see details on the back of the tank. I did a 50% water change, which seemed to help, but it clouded back up again. I added a bunch of polyfill to the AC 110 I have on it, as well as a bunch of carbon (the stuff that came with the 110, rinsed for a few minutes) and more polyfill in a cheap Tetra HOB I picked up at Petsmart. After roughly 24 hours, I haven't noticed a change. The fish seem fine, and corals are okay (unhappy about the change in PAR from the lights, but that's it, I think). I'm mixing up another 50% water change as we speak, but I'm just wondering if anyone else has any suggestions? I'm not sure why the saltwater tank freaked out over the generic purigen when the freshwater didn't, although it could obviously be a totally separate issue, but that would be a heck of a coincidence! At first I thought maybe I just hadn't rinsed the stuff enough, but if it's been in a filter for several days, I would think that would have rinsed it out, and the 50% water change would have fixed things? Either way, I removed it for now.
Thanks guys!

gbroadbridge · Feb 11, 2025

Purigen is some type of polymer resin.

I don't know if there is any way of determining the type of another resin.

Did it say it is suitable for saltwater?

Maybe @Randy Holmes-Farley can provide advice.

TMF89 · Feb 11, 2025

It did mention it was for both fresh and saltwater. Copied the description, and while not exactly written by a native English speaker, does seem to basically claim it's Purigen, and several off the reviews mention they use it as a replacement for it. FWIW, it showed up as the light yellow color, and still looked that way when I removed it from the tank. Tank is still murky, going on about 48 hours now, with a bunch of carbon and some Polyfil added to the filters. When I crank up the white LEDs, the water looks like it might have a slight green tint to it? I think I rinsed the carbon well enough (several minutes in tap water), but even if I didn't, it would cause a black/dark tint I would think, not a cloudy green one? Going to do another 50% water change tonight or tomorrow, and throw in a cheap UV sterilyzer on the off chance it's some weird bacterial bloom? Fish still seem unaffected, same with snails and crabs from what I can tell. I only have a few zoas and a kenya tree for corals, the zoas are slowly retracting but still mostly open, and the kenya tree has been pretty much shrunken closed for the last day or two.

For what it's worth, my RODI media is roughly 1 year old, but TDS meter still shows 0-1 on the outflow line. I've heard sometimes maybe you can still have issues with water quality even with TDS showing okay? The only thing I changed before I got the cloudy water was adding the generic purigen, but maybe it was just bad timing with something else? Not sure at this point. Thanks guys!

ENHANCE WATER CLARITY --- This filter media is an organic filtration resin which is developed to remove nitrogenous compounds and waste produced by fish, corals, and even plants, making your water crystal clear.
FOOD GRADE RESIN PROVIDES PURE WATER --- This special filtering material is not a mixture of ion exchangers or adsorbents, but a unique macro-porous synthetic polymer that removes soluble and insoluble impurities from water.
ADVANTAGE --- Being both spherical and macroreticular, it has microscopic pores that increase its contactable surface area to many times than most spherical resin. Age Range Description: All Stages. Rinse before use.
REUSABLE --- Color changes from light yellow to dark brown, even black while it adsorbs the waste. Once it is exhausted, it can be regenerated with a solution of bleach and water.
Convenient Usage --- Easy to use 2 Bag each pack 300 ml, simply unpack and it's ready for use. The mesh bag design ensures no leaks, making placement even more convenient.