Ok thanks, do you know of any makes that are free from phosphates?, to test a product would it just be a case of adding to RO saltwater and testing?
I would love to be able to grow cheato and other types of algae but i dont have a sump, one thing i did think of is putting some in the rio 400 filter and removing the top cover so some light can get in, would this be a possibility or would it grow to the point where it could clog the powerhead up?
I have also posted another post about a filter rack which could enable me to have a small sump without drilling, but i am unsure on the logistics of these overflow type things.