This is good reading. Just to give you an idea. I have been using Marine Environments for 2 years and here is what I have noticied.
Every time I mix a 50 gal bag and the parameters are on the money. I mean every time.
I like my water at 1.026 so I mix 47.5 gallans and bingo 1.026
ph and alk are on the money every time. Alk is a little low for me so i add 1 table spoon of baking soda.
My tank is very healthy and I grow xenia/ric and clams like crazy.
It is funny the xenia and mush all open up when I do a water change.
I have never had a bad batch!
Granted it is a little expensive but you get what you pay for. I belive the top 4 are made by the company as well. If in doubt, give them a shot and see for yourself
Ohh and I just started adding CA since I have sooo much requiring it.