My friend's nephew(8 years old) said that he like the look of algae so much that it put 2 guppies in a 1 gallon and left it out in the sun for a few days and it bloomed with algae. He really liked how it looks because the algae cover the rocks and stuff but I thought this was a bad ideas. My question is that can any fish live with all that algae? Because it covers the rocks and gravel and everything. Not a good sight to me IMO but he likes it.