My daughter was having problems with her tropical tank. The tank is not heavily planted, no plant debri, gravel is kept vacumed lighting is okay, not too many fish. Reasonably regular water changes. She had problems with black algae and after treating and replacement of tank decoration eventually got rid of it. We then got rid of the internal filter and replaced with a larger external canister filter.

A few months later she started having problems with green cloudy water (single cell floating algae). I got her to increase her water changes but it only slowed it down. I eventually went over ( I live in Gisborne, she live in Hamilton) with a UV light attachment for her filter and we had success.

Unfortunately the last trp I made she is now having problems with what I think is blue green algae. She is not having much luck getting rid of it, considering how clean she keeps her tank, how do you deal to the blue green algae and why does she keep having these problems. I have advised her to increase water changes, treat withSera baktopur direct and turn off lights for a week while treating.

Are there any other suggestions?

What is the photo period?

How much is she feeding?

Greenwater is caused from excess nutrients and lots of light.

Cut the lighting period a bit and see what the green water does.

About 10 hours a day for lights, and no she does not overfeed.

I would cut back the lighting to a couple of hours a day, then slowly build it back up to round 8 hours.

Agree with above but also algae can be cause by too much phosphate over nitrate. The phosphate arrives via the food and the nitrate can be removed by the plants therefore water changes will help.

Thanks I will pass that on.