Brightwell Aquatics Remineraliz - Adds Minerals to Distilled, Deionized, or Reverse Osmosis Water for Freshwater Aquarium Use 500-ml

I puchase this product once a month for my RODI Water. It is a necessary item if you use RODI water for tropical fish. I have very tender species of tropicals that I cannot use ro water with. This product maintains the proper mineralization without being harmful even with accidental increased dosing. It works fine with buffers of any kind. I raise betta fry in the water with this product which is amazing how much difference it makes over other brands of remineralizer. This product is easier to find than other brands plus the price is reasonable if you follow the dosing. One 500 ml bottle lasts me for aprox 1000 gallons. Excellent product for the price.

Love this product. I hate what powdered calcium supplements do to my planted aquarium. This product prevents that dust.

First of all my bottle was not sealed and was leaking, only approx. 5 ml. was missing but that's not the main issue. When I try a new product like this I like to set a base line with one gallon of RO Water. I started with 1ml of product in one gallon and nothing. I kept adding 1 to 2 ml at a time and testing until I reached 40ml and got no increase in dGH. I tested the product straight out of the bottle and only got a reading of 1 dGH in a 5ml sample. I thought this would be my answer over using powdered products but not where you have to empty a whole bottle in a 5 gallon bucket of RO water to do a water change in a 20 gallon tank. DON'T WASTE YOUR MONEY ON THIS PRODUCT. UPDATE: I returned this product for a replacement thinking I just received a bad batch. My replacement bottle was exactly the same as the first. Don't waste your time and money on this product!!!!

the numbers were off for what it advertises at the recommended dosage.

Avoid! I have a planted tank and use ro/di with it and my reef. I weighed out 4g of ro/di water, 0tds. I added the suggested amount for 6dkh but it tested low. Tank is 6dkh for reference. I ended up adding the WHOLE bottle to the 4g of RO/di water and it tested 7dkh finally. I shook the bottle well of course and validated the dkh test against another test kit and my other tank. Buy anything else or just use baking soda for sodium carbonate. This is literally just water. Been a long time since I had an aquarium product this bad.

Like many reviewers, I use RO/DI water for multiple aquariums. Thought I would give this a try, not sure if I got a bad bottle or what, but to quote another reviewer, not entirely sure what I got wasn't just a bottle of water. I like to use 1 gallon of water to come up with my "recipie" and then I can expand it out from there. 5ml should move the GH up on 20 gallons per the bottle. I added small amount of this to 1 gallon of water, then more, then more.... I got up to 100ml in 1 gallon of water and GH hadn't moved an inch! Let it sit over night. Nothing. Went so far as to buy a new test kit. Nothing. My take, don't waste your time.

I think this is just water, and it did NOT measurably change GH or KH in the RO water after double, tripling, quadrupling recommended dosing. Yes, I shook the bottle well. Yes, I waited an hour. The additive did NOTHING to the water.

My batch was no good… did not come close to raising Gh in my rodi water… even tried a higher dosage on 2 cups of water and saw only a small increase in Gh