Kolar Labs GFO Bayoxide E33 Phosphate Remover – for Freshwater and Saltwater Aquariums, Reef Tanks, Promotes Coral Health, 250g

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.

I tested my saltwater phosphate. It was 0.06.. a week before installing this product. Tested this week. Phosphate is 0.03. I like where it's going now.

Did what its supposed to do! Dropped them phosphates like it was hot!

Water sorting application.

Works great.

I don't normally leave reviews. I just recieved product yesterday added it yesterday. It is a powder substance with fine particles. Put in reactor and turned flow down where it tumbles nicely. Po4 was 0.22 and sometimes 0.33 always high. Haven't been in reactor not even 24hrs po4 was 0.09 with hanna checker so it must work. I'm happy with it

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 read the other reviews but thought if I took a few precautions I could mitigate the dust. I was wrong. I started by sifting the GFO through a super fine strainer. Then I soaked it for 24 hours. Then placed the reactor in a 5 gallon bucket to start it. I think about 1/8 of the 75 grams I used ended up in the bottom of that bucket. TyT being said once I was able to get it to flow clear it seems to working great.