Kolar Labs GFO Bayoxide E33 Phosphate Remover – for Freshwater and Saltwater Aquariums Reef Tanks Promotes Coral Health

I’ve tried several brands of GFO over the years, and Kolar Labs’ Bayoxide E33 is easily one of the most consistent. It’s clean right out of the jar — very little dust after a quick rinse — and it doesn’t clump or break down like some cheaper versions. I’m running it in a reactor on my 150-gallon reef tank, and it keeps my phosphate levels stable around 0.03–0.05 ppm. I noticed clearer water within a few days and no negative effect on corals. What I like most is how long it lasts before needing replacement — easily 6–8 weeks depending on bioload. Pro tip: rinse lightly with RO water before use, and use a slow tumble in your reactor to avoid grinding it down. If you’re serious about keeping algae under control and your colors crisp, this GFO is worth every penny.

Works great, lowered phosphates in a few days of use

Very dirty, must rinse very thorough

It just works perfectly! I'm using it in a two little fishies reactor, so I don't have the dust problem described here with some users, and I discarded the water right when I turned it on in a bucket. Recently I had to change my whole marine tank, so I was dealing with lack of bacterias and adjusting all parameters, and my tank started to look brown at some point. Within two days I had the reactor on with this GFO, and it's all white and clean again! Hope it lasts too. But so far, it's just impressive.

I use this in my 20 gallon long reef tank. I mix 2grams per gallon which is 15 after accounting for rock in a boyd media bag with almost half cup of black Diamond carbon and zip it with a reusable zip tie and place it in one of my two AC50’s. I change it out monthly and my PO4 is always 0.02-0.00, crystal clear water and zero algae issues. I do squeeze it around in my weekly water change to keep flow good through as it never clumps and I do place a little filter floss on top to increase water contact. A lot cheaper to make your own CPE and don’t need that waste of DI resin that they add as you should be using RO/DI to begin with......