ok i don't know if this is going to be a stupid question or not but here goes. what is the difference between the dark purple and the light purple coraline algae?
There is not a lot of difference- coraline algae does come in many colors. from my experience, the darker colors tend to reuire less light... i had LOT of dark dark purple coraline when i was using NO bulbs, and when i upgraded to VHO, all the dark purple only grow in areas that are in the 'shade' now.