
I have had cherry shrimp, for the last year. I had 4, the last one died just recently

I have some dwarf puffers which I have never witnessed harass the shrimp, and threadfin rainbows. I have been wondering whether or not to use ro water to do water changes, as I am getting a lot of algae in the fish tank, I think because of the phosphates introduced when feeding the dwarf puffers frozen bloodworm, would a tank with ro water harm shrimp? because i'd like to get some more shrimp. I think someone said to add a little tap water to ro to put some trace elements back into the water, but I cannot remember the percentage.
sorry for the long post.