Bayoxide E33, GFO Phosphate Remover, Granular Ferric Oxide, For Saltwater Aquariums

As several others have noted, the granularity is very fine, and there is a fair amount of product dust. This really needs to be used with a media reactor, not just a filter bag. The larger the reactor, the better, so as to let smaller particles fall back down.That being said, this product is at an excellent price, and controls my phosphates well in my 300g mixed reef. When phosphates start to climb, for the first time, I just top off what is already there with another 1/2 - 1 cup. This gives me a little more time out of the product as a whole, rather than just throwing the entire contents out.This is my second purchase of this product, and everything has been consistent.Hope this review helps others.

The product works as described, but it is very dusty. I've used granular GFO before and do know what to expect but a good portion of my jug is a lot finer than granular, more like powder in most of the tablespoons. I had to drastically reduce my flow through the reactor to prevent GFO from being pushed out of the reactor itself. Even using additional foam did not prevent the product from entering my sump. Again, just reduced the flow A LOT in order to prevent that. It is, in fact doing the job which is what I wanted. Just wish it wasn't as dusty and contained more granules. I would consider purchasing again as I prefer granules to industrial grade personally.

I rinsed the product out, or so I thought. After placing it within my reactor it made more dust, and more until I had to shut off, rinse again and put fine micron bag filters to eliminate the dust. Skimmer was working overtime. Rinsed again, still dust, and I’m talking about enough dust that you couldn’t see the other side of a 24” deep tank. Tank is a mess. I’m talking a ton of dust so I think the GFO is more or less being dissolved or pulverized, this isn’t just dust from settling in shipment - no way.

Unlike Bulk Reef Supply's GFO, I decided to try another brand, and unfortunately, it's just 95% dust, cakes together like sand in my reactor. I used it three times (replaced 3/4 cup every week) in my reactor, and barely noticed a drop in phosphates vs. the BRS GFO (which I was using the high capacity version). The pure dust is just irritating, and as a result, the rest will end up in the garbage.

I have been running reef tanks for over 20 years. This is hands down the worst product I have ever bought. I literally spent over 50 gallons of RODI water rinsing the dust from 4 pounds of this trash and it’s STILL filthy. I have a 750 gallon system and after 5 minutes of running this through my reactor I can’t see 3” into my tank. Do not, I repeat, DO NOT waste your money on this inferior product. I have never, in all my years of reef keeping had a product fail so badly. Please learn from my mistake and avoid this product like the plague.

I used mesh bag, added about a half a cup worth and put it in my canister filter. Worked great. I had somewhat high phosphate and after about a week, they were completely gone.

Can’t tell if it’s doing much or not. Had to had two urchins, a lawnmower blend, and use this gfo to even put a dent in the algae.A bit dusty. Can’t complain I suppose

Great price for GFO and works like the more expensive brands.