I have a 25 gal tank Would like to put a skimmer the outside hang on type. i had a Seaclone on it and it was nothing but trouble threw it in trash kept the power head only thing that ever worked on it. I'm having trouble with Cyno it's green and is on live rock and on the sand bed. kinda like a blanket on sand you can push around. Was looking on line and would like something not expensive that works . my tank is rectangular not a nano. Local shop advised i should start skimming again to improve water to alleviate the Cyno if that is what it is problem.
Ronny
Ronny