So a looooooong time ago, Matt told me he was given a large container of (at the time) new Phosphate Out Pro by Aquamaxx and was asked to do a review. It is a form of GFO and Matt doesn't run GFO so he asked me if I could do it. Without really thinking, I said, "sure! I know I'll need it." Of course this was about the time that I was: - Doing a down-to-studs remodel of my new house - Moving into said house. - Setting up my new 5' x 5' 370 gallon system. - Moving my old dual 175g tanks into the now-consolidated 370. - Setting up a refugium - something I had on my old system and have yet to do on my new. This is a key omission. Needless to say, far too much time passed before I was able to even think about both setting a reactor (Matt also passed along a little Phosban reactor) much less writing a review. Well, necessity drives all things and my necessity turned out to be dinoflagellates. My phosphates had been climbing since I set up the new system and I began to see some cyano algae begin to take hold. Then the sliminess combined with the little bubbles (the dinos) started appearing. Before long I had one very ugly tank taken over by slimy sh!t. Not exactly what I had envisioned when I spent all that time and money putting this new system together. Dinos are a pain to get rid of, but they also thrive off of high phosphates so I knew my first task was to get my phosphates in line. Product Overview From the Aquamaxx web site: AquaMaxx Phosphate Out Pro is a high capacity granular ferric oxide (GFO) adsorptive filter media that removes phosphate from aquarium water. Phosphate is a fuel for algae growth and can also inhibit a coral's ability to utilize calcium in water. Phosphate Out Pro does not leach phosphate back into aquarium water after it has been absorbed by the media. Phosphate Out Pro holds up to twice the amount of phosphate compared to standard GFO. AquaMaxx Phosphate Out Pro will have an effect on your alkalinity level, so be sure to test your water regularly as you would with any phosphate removal media. For best results, use AquaMaxx Phosphate Out Pro inside a canister, hang-on back or other aquarium filtration system. Using a filter media bag is strongly recommended. Phosphate Out Pro can also be used in fluidized (up-flow) media reactors. A ball valve is required to regulate a slow flow rate through the filter to prevent granules from becoming pulverized. Steps to Lower My Phosphate Levels I had very few illusions about a little Phosban reactor actually lowering phosphates on my 370 (total volume ~ 500g) regardless of what I put into it. So first I bought some Brightwell Phosphat-E liquid phosphate remover to get the phosphates to reasonable levels. Then I figured I'd see if the Phosphate Out Pro could keep the levels steady. I know this is a review about the Aquamaxx product and I hesitate bringing the Brightwell product into the mix, but they do perform very different functions. The Brightwell product does nothing to maintain levels in the tank. It is a series of single (relatively expensive) "hits" to phosphate levels. I must say that I like the product and typically use it at the first sign of cyano to drop levels, but it is rather like taking Dayquil for a cold; it will temporarily deal with the symptoms, but do nothing long term. For long term maintenance, you must deal with what is causing phosphates to rise (not always easy), put in a maintenance mechanism (e.g. gfo reactor, refugium) or combination. After a few doses of the Brightwell product, I got the Phosban reactor set up and put the Phosphate Out Pro into it. First I have to say that I DETEST dealing with GFO. Here is why: - If you want to stain your new deck a rust color, just run water through a little GFO, you'll get enough in the wash to cover your deck, your neighbor's deck and maybe the one for the new bar down the street. - No matter how much you wash it, the rinse water still carries particles. Once hooked into the system, particles still get into the water column. - The granules tend to be just the wrong size. They are big enough to clog drains, etc., but too small to deal with spills and so on. Enter Phosphate Out Pro. When I first went to do the prewash, I was dreading it. I knew I was going to be staining my utility sink, the media would get into the drain, my t-shirt would look like I just stained my deck and rubbed my hands all over it... but when water started flowing through, I was sure something was wrong. Where was the thick red staining water? Where was all the hassle? Yes, there was some small amount of debris that came out in the rinse, but even that was less than just about any other media I've dealt with. I was absolutely shocked that it took very limited rinsing with next to zero run off before I could use it on the system. Additionally, for whatever reason, it just seemed easier to manage than other GFO I've worked with while handling. So not only is the media supremely easy (and clean) to deal with when putting it into the reactor, but by definition, it also isn't sloughing off into the water column to the level of other GFO (and many other media types). The Results The little Phosban reactor was obviously too small to really have any effect on my relatively large system so I decided to buy a larger reactor along with more Phosphate Out Pro. Well, a little more than a month later, the new reactor is still in the box looking for another job and the extra product is sitting unopened on my shelf. The cyano is disappearing, the dinos are receding (I also upped my kalk dose in conjunction) and my phosphate levels are actually dropping with just that little reactor. I could drop them faster with the larger reactor and more product, but frankly I'm too busy to deal with it. It's working as-is so I'm sticking with it. Summary - Pros and Cons Pros: - Very easy to work with - far and away better than any other GFO I've used. - NO STAINS! - Super easy to rinse with very limited run off. - Less GFO gets into the water column. - It is highly efficient at its job. Even large reactors with other products did not have the same effect. Cons: - The only con I can list is cost. This product is very expensive. Overall I am thrilled with the results I've had so far. I think the true test in reviewing a product is whether I would continue to use it on my system. I have to say that the answer here is an emphatic YES! The expense is at least partially offset by the facts that you will use less and you don't need as large of a reactor. Those combined with the ease of use and less getting into the water column (always a little bit of an issue for me with GFO) makes this a no-brainer decision.