How long to wait in adding fish after losing some?

[samelewis]

Greetings everyone.

A couple of days ago I lost (probably all my fault) 7 out of the 9 fish we had. It seems my red fantail goldfish ate my bala shark.:sad

The day after the bala shark died, all 4 goldfish and the 2 platys died.

Anyway, how long should I wait to add fish. I want to make sure that the water is not the culprit. I did 1/3 water change after all the fish died.


Just test the water:

Amonia - 0, Nitrate - 40, Nitrite - 0, Hardness - 250, Alkalinity - 180, and the pH is 7.4.

[Slappy*McFish]

Do a few more water changes and try to get your nitrate levels below 20.

[yhbae]

How big is your tank? It certainly doesn't sound like nitrate killed your fishes....

[Aquarius0015]

Goldfish with tropicals? What's your water temperature? Goldfish need a lot of water per fish, so your tank should be pretty large to accomodate 4 goldfish.

[samelewis]

yhbae - I have a 29 gal tank. I am thinking this is too small. I had planned on buying a 100gal tank for christmas, but a little to late, I guess.

Aquarius0015 - The temp has been fluctuating between 72 and 74. Is the temp to low? I have been using the same parameters for the tank for 3 months now.

Any help would be appreciated.

Scott

[SnakeIce]

those temps(72-74) are in the lower range for tropical fish. I believe that gold fish need a bit cooler water. unheated or mid 60s is better for them and they can survive near freezing temps for a season

[yhbae]

This one is puzzling - I'm assuming they lived ok for the past 3 months in the same tank? (Gold fishes shouldn't be mixed with tropical fishes, but why die on the same day?) Your tank is certainly fully cycled...

Are you sure that you didn't accidentally add any chemical/substance or any objects into your tank recently?

[samelewis]

The only thing that was added, was a bublle wall, about 5 days prior. I made sure everything was rinsed off really good before putting it in the tank.

Think I will take this a lot slower than before, and due a lot more research.

Thanks to everyone who responded.

Scott

[Aquarius0015]

Did they all die at the same time? Perhaps one died when you were away for a few hours. The dead fish would begin to decompose and release ammonia which would hurt the water conditions for the other fish. Your tank may have already been overcrowded (which depends largely on the size of your fish) as goldfish are very messy and require lots of space. Also, the temperature is a little low for tropicals and a little high for goldfish. These factors may not be lethal individually, but combined, who knows?

But this is just a maybe, because your ammonia readings are at zero. Then again, if you waited long enough after the deaths to test, the ammonia might have been converted already by the biofilter.

I doubt the bubble wall was the culprit, although if you somehow had toxins in the air, the airpump could easily introduce them to the tank.

[samelewis]

Aquarius0015 - I must admit, the last test were done a couple of days after the fish died. I would say that half died the day the shark died. The rest (except the corys and snails) died later that night.

As far as the bubble wall, I agree with you that it probable was not the cause. I have since put it back in, and the corys just love it.

I tested the water again (saturday), with roughly the same outcome as my first post.

Thanks for the help and advice.:D

Scott