First of all, the product does seem to work by some degree, but the rock water of LA county seems to give it a real run around and does some other odd things. This review touches two different topics. If you are at all serous about keeping fish, to hear my tapwater is naturally PH of 8.2 will make you cringe. It also has a KH of 5 and a GH of 7 by the API test I have. I keep a 10 gallon tank that is lightly planted with a dirt and aquasoil substrate. The directions for the product say to use 1tsp for a 10-20 gal tank to maintain a PH of 7, "or more as necessary," of which I mix into my changing water. Here's the kicker though: I use 1/2 tsp per GALLON to achieve only a PH of 7.6. That is what? 500% the recommended dose? And that is just the straight tapwater in a gallon jug I use during water changes, not actual tank PH (which has never been below a 7.6 save for about a 6 week period when I added Fluval Stratum, to which now has burnt out and stopped buffering.) And although it doesn't seem to change my GH, it sure does change the KH of the water, going up to a 13.5, which in some ways makes sense, but still! Further more, in my test so far, it seems doubling the dose to 1 tsp for a gallon of water and letting it sit gets me a reading of maybe 7.4PH, and the KH doubled yet again. Seems like a lot of product to achieve minimal returns in my circumstance. In the future I may try getting Seachem's Acid Regulator to more aggressively attack my PH issues. By this point, my 1 yearold fish are acclimated to the elevated PH and do well enough, and sometimes show breeding behavior, but should I really want to take my hobby to the next level, I will either need to figure out how to lower the PH more, or give up on tropical fish and go saltwater... That all said, I will continue to use the product for now as it works better than the Petco brand PH reducer I had given up on, and has had a sudden, unexpected change upon my tank I want to explore more. If you have a planted tank, this may be of interest to you: When I first got the product, I read the label and directions, but some how failed to see that it also removed chlorine and chloramine from tapwater, and continued to use the dechlorinator (Seachem Prime) I already had along with it for the first few months. Then just a few weeks ago I read the bottle of Regulator again and realized I was double treating, so decided to use Regulator only for a waterchange of my semi-regular 30%. To my surprise, the following week there was a huge change in plant growth, up to a whole inch of new, large and healthy growth. My stem plants look like palmtrees now, cause they were nothing but sticks with a few scraggly leaflets that were all to short lived, and now suddenly are branching out in full size! For a whole year I had been struggling to keep my plants alive and growing, I gave some liquid fertilizers a try, I tried doing more regular waterchanges, I tried doing less waterchanges, added to the tank new aqua soil. Nothing. Plants that once did fantastic were just dying off without answer, including the damn duckweed! You know something is wrong when duckweed is struggling! But the week I used only Regulator, sudden improvement to my remaining stem plants. It may be a fluke, but I am chasing this idea and logging it, and will update my review over the coming months should it be false or true.