Thank you so much, I didn’t think I needed prime or stability but just wanted to make sure. Do you know if equilibrium is dangerous if not measured exactly?DutchAquarium said:I wouldn't use those other two. Firstly ro water is devoid of minerals and therefore, yes you need the equilibrium. Seachem prime is a dechlorinator that would only need to be used if you were using water from a tap. the ro system takes chlorine out of the water, so you don't need it. Stability isn't needed either because you don't want to be messing with your ph unless you plan on being extremely on top of it to keep it from varying. The important thing about Ph is keeping it stable. You don't want it to varie, otherwise this causes stress.