i need help now

[draco]

that makes sense. no i top off with fresh RO water, but i do my changes with tap water. i think i may be through most of this now. my leather coral is standing up more and my water is clear. however my 2 firefish and my jaw fish did not make it through this. my clowns are back in the tank and doing ok so far. i am still looking for any advice, you can never know everything right. and i dont want to mess up again. i am off for a boxing day sale is it worth looking into a new filter, i am not familiar with the canister filters. i have a fluval right now and i dont like it. also i noticed from running my friends coralife skimmer that it is pulling more out than my prisim. any comments?