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

 

[msjinkzd]

does it get any light from windows, directly or indirectly?

 

[verbal]

What is his water change schedule? Does he have nitrates in his well water?

 

[Avatar]

Light + nutrients = algae

Next thing that occurs to me that it sounds like the water is very still as the algae that live in ponds are different than the types that thrive in streams and attach themselves to glass, rock and plant surfaces. Also sounds like the filtration is weak. Your friend has an abundance of nitrates and/or phosphates in his/her water probably coupled with excessive light. Options:

1) Take some well water to a store and test for both groups of chemicals;
2) Reduce duration of lighting;
3) Reduce intensity of lighting.

The lattermost option can be achieved in many ways, i.e., changing bulbs, pulling down the window shade, reducing quantity of bulbs, or my favorite, using floating plants (like water sprite -Ceratopteris thalictroides - which also does well planted in the substrate) to screen/block the light and absorb excess nutrients.

Pretty simple. You could also look for some freshwater filter feeders though its a not a niche that has fostered many species.

 

[Tony]

Sound advice above. If those options fail, you could try a UV sterilizer.

 

[mchambers]

Some more ideas

Sound advice above. If those options fail, you
could try a UV sterilizer.

Some of the same ideas, and a few more, are linked below:

http://www.guitarfish.org/algae#greenwater

 

[twisted fisher]

Get an oto or ABN lol no more algae!