You need to test for PPM's of your water. Too much chlorine is bad. Well water with too much iron is bad. You can let water sit out to get rid of chlorine. I would get even a cheap filter to help and then a little cal-mag plus.

It helps if you cover the hydrotron but like said just keep the roots in the dark. I get a little algea sometimes but algea won't hurt unless it's a massive break out.