Originally Posted by jclee

If you don't have any nitrates, the tank hasn't cycled yet (unless it's just a faulty test kit? It does seem strange for it to be uncycled after 3 months).

1.) is the tank getting direct sunlight?

2.) have you been adding anything to the water?

I'm not sure what to suggest except to keep manually removing as much as you can, and try to figure out what's helping the algae succeed, then remove/reduce that variable. If you're pretty sure that high phosphates are causing the algae, frequent water changes should help, right? Where do you think the high phosphates are coming from? Could they be leaching out from decorative rocks?

After the tank's fully cycled, it might be worth reading through the threads on algae eating tank inhabitants, though no one solution would help with both types of algae.

Good luck. I hope someone else comes along who can help a little more than this.