Brightwell Aquatics Phosphat-E Liquid Phosphate Remover for Marine Fish and Reef Aquariums - Aquarium Water Treatments, 4.2 fl oz

I have a 300 gallon mixed reef and the phosphate level got away from me probably due to overfeeding. When I bought the Phosphat-E, the level tested with a Hanna Checker was 1.9 ppm.Having read so many excellent reviews and only a few negative ones, I felt that the overall product is good, but also decided to go slow just as the instructions state. It provides a maximum dose, but I saw absolutely no reason to take a chance since it saws its best to lower the phosphate level over 7-8 days.The simple math indicated a total (max) of 37.5 mls per day, but I started with 10 mls split into 3 doses, morning, midday and early evening. No negative results at all and the next day I couldn’t believe that some of the closed polyps were beginning to open back up. I increased the dose to 12 mls for the next 3 days and after 4 days, I tested and the level had dropped to .09. I again increased the dose to 16mls as the corals are looking so much better. The phosphate level at day 6 is now .06 and I am confident in following the “go slow” approach per the instructions. I should mention that I also cut down the feeding quantity and although fish will eat all day if you feed them, they are still happy. 😊Overall great product, easy to use, and I highly recommend.

Works. Be careful about the dosing

A good value easy to use works great

This stuff might be great, I can’t tell yet, but I have a real issue with the dosing instructions. First, I understand the dose is based on the amount of desired phosphate reduction in a given volume of water. I get that. But you have to do the math to figure out the correct dose. “Each ml eliminates 1ppm phosphate in 4 gallons of water.” Ok, I have 40 net gallons of water in my tank and I want to reduce my phosphate by 0.2ppm. What’s my dose? I have to do math to figure that out. I don’t want to do math. I want to read a chart that did the math for me. Nope. They don’t provide one, not even on the web page. Still, I can do the math to figure out my dose. 1 ml will remove 1 ppm in 4 gallons of water. So...1 ml will remove 0.5 ppm in 8 gallons1 ml will remove 0.25 ppm in 16 gallons1 ml will remove 0.125 ppm in 32 gallons1 capful (5 ml) will remove 0.6 ppm in 32 gallons. Here’s where my dosing goes south on me. The directions on the bottle also say 5 ml will remove 1ppm in 40 gallons of water. How can 5ml remove .6 ppm in 32 gallons and 1.0 ppm in 40 gallons? If only that had a, what’s it called, oh yeah, A CHART!***two treatments later***I still don’t like the instructions and all my earlier complaints about determining the correct amount of liquid to use but...the stuff worked. Like, totally worked. According to my API phosphate test my levels have gone from >1.0 ppm to unmeasurable. Nothing’s died in the tank and I’m happy with the outcome.

I've struggling with phosphates for awhile now and did all the things, aggressive water changes, all sorts of filtering and feeding changes etc. This stuff had me back to near zero in no time and suddenly corals are growing again. Well I shouldn't say no time, I had no change after the first several days, then it dropped dramatically to not measurable very quickly. As far as I can tell there's no downside.

I tried this product a few times and every time my corals loose color and or die.

This stuff just works! I have had phosphate issues in my reef tank forever and have tried everything to get my phosphate to come down including nuking my tank on more than one occasion using NOPOX. I now have my phosphate under .05 and good coral growth. The only downside is that this will drop your PH and ALK a little but both will come back up in about 48 hours. If you have phosphate issues this is the only product you should be using!!

DON'T OVER DOSE! If you follow the direction, account for water displacement, and don't over dose this stuff is amazing. My PO4 was over 1ppm, as my kit only measures 1 or 2 or 10, it was hard to get an exact number. So I dosed the maximum for my tank 2.5ml for 20gal. The next day it measures at .77ppm, I dosed again at maximum for my tank, and just like the bottle described it dropped exactly .25, I know this because I have a ULP Hanna tester, my new measurement was now .52ppm, I have seen no shock in the coral, inverts, fish, or macro algae in my tank. So morale of the story, follow the direction and it will work as advertised perfectly.