i guess the shrimps are doing a great job. i also have 2 oto in my tank, i think they help clean the tank from algae but most of all i guess when you have a balanced tank, there will be no algae problem
i don't do very much with that tank. just feed the fishes and trim some of the valis if they grow too long and curl up against the glass.
best tank i'am keeping as of now. just add water and feed the fish hahaha