Dead Fish!!! Aaaaaarrrrgggghhhh!

[Thaiboxer]

Here's the short version...

Cycled my new 55 gallon tank with Danios and a betta, all went well and Ammonia and Nitrites finally got to 0 New Years day. pH has been constant at 7.4. Went and got:

2 Dwarf Gouramis
8 Rummynose Tetras
Guppies - 1m and 3f

I added these all to the tank, and all was well the first night. The next morning I noticed that the male guppies tail was chewed up a bit, so I removed the betta and kicked myself for not doing it sooner.

I watched Ammonia and Nitrites closely, never saw a spike. On 1/2, one of the tetras was found dead, looked like he had his face bit off. I wasn't happy about that, but hadn't seen any aggressive behavior from anyone else.

The next day, 3 more tetras were dead. No sign of ick, swollen stomach, or abuse at all! I removed the remaining 4 tetras to a small hospital tank. Saturday morning (1/4) 3 more were dead. I now have one tetra left.

The male guppy and one female died also, but I think that was from the abuse from the betta earlier - not sure.

Everyone else seems healthy now. Any idea what's up with the tetras?

Thanks for the help!

 

[Grant R]

Sorry to hear about that mate.

Are you definitely sure that the tank had fully cycled, as Tetra's don't really make brilliant cycling fish, but Danio's do, hence maybe why the Danio is still alive.
I'm sure it had cycled if you say it had, but just to be sure - : )

The only other thing I can think of is that the fish you added was quite a large number and may have significantly disturbed your settled / cycled water parameters, causing the slow death's in the already stressed fish. Tetra's aren't really the most hardy fish out there unfortunately either.

Again, I could well be wrong, but they could be the cause.

Good luck for your next lot, sure it'll be fine.

G

 

[Bearfan]

I think the number of fish added all at once could be a factor. General rule I have for new tanks is no more than 3 fish per week for the first 6 weeks. This gives your aquarium time to adjust and not shock the system.

 

[Thaiboxer]

That makes sense. It had been about a month since the Danios and the betta were added, and the water tested out perfect with my kit at home and at the LFS.

Perhaps it was the shock of adding so many at once. I'm going to leave it as is for a few weeks before adding anything else, and see how it goes.

Thanks.

 

[Guest]

Do you know the pH and hardness of your water? Rummynoses can be quite sensitive when those parameters aren't in-line with what they like.

 

[Thaiboxer]

ph is 7.4, I think the hardness wasn't too bad but I don't know numbers on it right now.

Update - Cleaning the tank today, I found that one of my danios was VERY dead - probably a week or so. Could that be what was affecting my other fish, also? I can't believe I overlooked it, but doo doo occurs I guess.

I cleaned the tank well today, 20% water change, and tested - ammonia, nitrite, and pH are still in line.

 

[Grant R]

I'd say you're doing the right thing, but when the time comes to add the fish, just add a few at a time. I know it's harsh, but patients is the key !


G