*cringe* here comes the Ph debate.
I would suggest just going out and buying measuring spoons. I have a ring I use just for fish only. My powder is 1 teaspoon per 10-20gl of water. I am assuming yours to be about that. You have to add in A LOT to overdose the tank and if it is a 7.0 powder you are okay adding 1 teaspoon per 10-20gls of water. I have a 55gl tank and use 3 teaspoons every two weeks.
I have been through the debate once and felt horrible on here. I still stand by the fact there are some people in some situations that have to do something about PH. I know many fish learn to live in high PH and that is great. In some situations like mine my PH goes off the charts and I lost every pictus cat I tried to keep. My betta was fine and my latest betta in the 10gl with out correcting the PH is fine.
My pictus cats would always die. My LFS tested my water and it was fine. Except they said my PH was way to high. Pictus like lower PH and can live in higher PH like most fish can adjust. However the felt mine was to high (well above 8 ) and if I brought it down I may be able to keep pictus alive.
I cycled my 55gl before adding the pictus and got the PH down with the powder. I do 50% PWC a week and every two weeks add the powder. My ph has remained at 7-7.2 since November and I have 6 very healthy pictus cats. Every time I test it and the LFS tests it, it is the same and for me that is priceless.
I dont like having to add it, but if that is what helps me keep pictus cats alive so be it. I dont use anything in my tank but Prime and the 7.0 powder. I do dose liquid calcium every other day for the apple snail to use for his shell. It is not enough to change anything in my tank and keeps the snails shell in a lower PH from disolving.
Before attacking me for using such a treatment take into account that I have a choice either dead pictus cats or doing something about it.
The main debate is to have a constant PH. I have that and have had that for 6mo.