fish are dying one at a time

[molahs4]

Hi,
My husband and I set up our first fish/planted tank about a month ago and it has been a bit of a struggle keeping the fish alive. We have a 90 gallon tank and we get a fish death about once every three days. Our ph is fairly stable and there are no traces of ammonia or nitrites. We've had two breakouts of ich (only the tetras were affected) and one instance of dropsy with a albino raspora and we treated the whole tank on all three occasions. We are also struggling with out of control algae and wonder if that could be contributing to the deaths.

The current behavior for fish about to die is as follows:

isolates from the school
starts hanging out at the top of the tank
heavy breathing but no sign of dropsy
torn tail (looks like it might be munched)
eventually disappears from the tank

could our fish be under attack from the dwarf gouramis or other fish? We have zebra danios, cardinal tetras, harlequin raspora, cherry barbs, a plecostamus, 2 dwarf gouramis, siamese flying fish and rumy-nose tetras.
Any insight would be appreciated.
Thanks.

 

[morleyz]

Repeated outbreaks of disease and algae are usually indicative of poor water quality. I have a few questions though:

1. What did you treat your tank with for the previous diseases?
2. Have you taken a sample of your water to the LFS to have it tested?
3. How "planted" is your tank?

 

[molahs4]

We treated the first batch of ich with rid-ich.
We treated the second batch of ich with nox-ich.
We treated the Dropsy with kanacyn.

Our tank is heavily planted with hi-light but not so heavily planted that if counteracts the algae.

We have not yet taken our water to be sampled.

 

[Faramir]

Algae is seldom a health risk - some blue-greens can be toxic in nature but I've never heard of it being an issue in aquaria.

Are there any physical changes in the fish that die, shortly before death? Any wasting, loss of colour? Are particular species more affected than others.

This could be very hard to track down, but bear with us!