Algae problem in one tank

[rdub]

I have six 20 gallon tanks. 2 rows of 3. The tank on the top row, furthest from the natural light of the window, has a constant problem with algae. The temp, water and fluorescent lighting is the same as the others on that row. Any ideas as to why this tank would have constant problems or what I might do to remedy the situation?

[discuspaul]

Hard to say. - Do all those tanks have the same contents/usage - e.g. are they all unadorned, bare-bottom tanks ? Is there some particular room lighting nearest to that tank ? Pics might help.

[foggy01.1983]

You say the lighting and water is the same do you mean they are lit by the same light tube, for example one tube gives light to all the tanks or do you mean they all have seperate lights but have the same tube?

The same with water. Are the tanks filtered by a single sump or is each tank filtered separately and you mean the water has the same parameters?

If each tank is lit independently try swapping the tube for that in a tank that doesn't have a algae problem.

With the Filtration if they are run separately have you tested for nutrients like phosphates.

Depending where the tank is situated although the tank is furthest away from the windows, does it at any point get direct sun light hitting it?

If your not sure try closing the curtains for a few weeks and see if the problem gets better.

Steve

[rdub]

Each tank has it's own light and they are turned on at the same time each day.

The water has the same parameters. Tap water. Water changes are done at the same time so all parameters should be equal.

Each tank has it's own sponge filter.

No direct light from the window. It is the tank furthest from the window. Gets no direct sunlight.

The window blinds are closed 99% of the time.