I have a barebottom 90liter aquarium and there is a green dust algae build-up on the floor. Would it cause problem if I will not remove it? I only rely on lawnmower blenny as CUC. The place where I live is illegal to sell saltwater inverts.
unlikely to cause problems other than being ugly. I'd scrape it regularly, personally. That's a shame about the inverts, I use trochus snails in my bare bottom frag tank and they keep it tidy.