koralia 750
 

i boought a koralia 750 thinking it was the size down is there a cheap way of slowing it down or muffling the flow cuz it seems a little overkill in my 30 gallon and there is no safe spot for my hammer coral they wont open :(

You could try covering some of the holes along the sides. I've never done it but I've cut some off to increase flow, never tried to reduce flow. Even wrap part of it up with chaeto or something.

Maybe reducing the propeler with a dremel.