advice on using well water and algae in the water column

[CommunityAngels]

My buddy has a 40gallon tank stocked with 11 tropical community fish filled with well water kept at 72 degrees lit by a basic strip light over the glass top. The tank was cycled and has been operational for two months now. He assures me that the filter is adequate for up to a 60 gallon tank. The problem is that there is green algae in the water. The glass, fixtures and such are fine. He says the water is turning green on him.

I have been in the hobby my whole life and have never experienced this. Although our system are different, they are basically the same. The only difference is that I've always run undergravel filters and he is using well water. I have always used city water. Could well water contribute the the algae? Not everyone uses undergravel filters, so i doubt it is that. What are his options?

Thanks for the advise,
Brian

 

[Avatar]

Water circulation/movement might help a lot for openers...

...as the algae that make the water green are typically different species from the ones that grow on the side of the glass or plants. Cutting down the amount or duration of light is simplest, maybe test the water for nitrates/phosphates if you're into that sort of thing. Another quick fix is to get some floating plants (water sprite is my favorite) to absorb/block some of the light.

Basically you have a combination of too much light and excess nutrients which is what I should have said first. And I'm guessing water that isn't moving and/or being filtered very well.