Guppies, interesting I didn't realize. Keep us posted on your success. People say mollies are good at eating algae I didn't notice any difference. They do eat poop 24/7 though.
Normally it's fish that that inhabit estuaries that have a mix of fresh and salt water. Other word "brackish water". Guppies does raise an eyebrow. This is the first white/silver Sailfin I've seen. Usually it's black mollies used. Might be the reason this one wasn't seen eating algae so much.