Turtle Tank - Dark Brown Algae

[Crestfallen]

Hello!

We have a 2 year old Chinese Golden Thread turtle. We have a 90 Galon Tank, with a fluval 405 filter. There are approx 6 fish in the tank (all tetras) and another 3 bottom feeders.

Just recently we noticed that a very dark brown algae is growing on some of his rocks. We have a lot of big river rocks in the tank.

The only thing I can think of is that we have a new (big-ass) halogen light (meant for fish tanks) above his tank.

But we have no idea why this started growing. Is this bad? We just removed it with vinegar after our weekly cleaning.

Thanks!

[Bina]

Howdy, I've sent you a PM with a link to check out.