Emergency evacuation

We are currently the proud owners of three aquarium fish: a red ryukin called Sushi, Ze who is a black moor and Sly, some fast fish. They all live happily in the state-of-the-art Bi-Orb.
Well, they did until yesterday.

I noticed that Ze was having serious problems staying below water. He had to swim furiously to get anywhere below the surface, most of the time he was just bobbing around at the surface. Closer look at the aquarium showed that there was a lot of algae and that the filter was really dirty, thus Ze feeling ill.
So at 11:45 pm an evacuation operation commenced. The fish were moved to a temporary bowl and all the water was drained. I cleaned the inside of the orb from accumulated algae and was lucky enough to have a spare filter to replace the grubby old one. We put Sly in a separate pan because we suspect that it is he who has been eating too much and producing too much, eh, stuff.
Sure enough, Ze started to recover as soon as he was taken out from the old nitrate rich water. We are still not sure of the outcome but will be putting back the fish into the orb later today so will see then.
Hang in there guys!
Update 14/09/03
The fish are back in the BiOrb and I am glad to say that they have fully recovered. Mission accomplished.
Update 22/09/03
Sad, sad… shortly after being put back in the BiOrb both Ze and Sushi contracted some kind of fungus infection. After 4 days of medication they passed away. Sly is still alive and kicking and we’ll be going to the pet shop this weekend to look for a new Sushi.