Guppy deaths...

[Tokis-Phoenix]

A couple of weeks ago i bought some guppys over a week period making a total of nine of them in my cycled 50gal tank which only had 4 albino corys and 1 5inch plec for about a month in it until they arived, making a total on 9 fancy guppys.

Over the last fortnight i have had 3 guppys deaths all in heavily pregnant females; when i first bought them my lfs owner did say he had been having some problems with them dying but i bought them anyway and didn't have any problems with them for the first week.
The first one to die was a very pregnant female that i was expecting to give any birth any day soon and then the next day she died. So i went through the process of checking water quality and everything pretty perfect; no ammonia, nitrites and nitrate, I did a 30% water change anyway.
It was pretty weird because non of the fish were showing any strange symtoms/behavior and neither did the ones that died. It was the same thing with the 2nd female who was also pregnant although i did find 4fry in the tank and only a couple of minutes ago another of my pregnant females has also died, only eating and swimming around happily one hour ago.
Water quality is still good and i have just medicated the tank a bit with some anti internal bacterial medication in case this is the cause of the deaths, i did a water change yesterday. It is so weird though! The water quality is good, the fish are showing no odd symtoms or behavior and the ones that have died have done pretty much instantly.
I am getting pretty desperate now as i only have 2males and 4females left and i havn't a clue on what is going wrong; the tank temp is 25 degrees. Please help me! any suggestions are greatly appreciated.

 

[Tokis-Phoenix]

Anyone? Anything...?

 

[GuppyDude]

alright heres my take on it. your water is fine, what is killing them is stress. they will not drop fry while under alot of stress, they will hold all teh fry in until they feal it is safe enogh to drop them. do u have plants or secluded parts of ur tank where the females can hide? being prego is stressful enogh, plus they had to deal with the probably nast conditions in teh lfs tank, and then they were moved to ur place. i think the stress of it all just killed them over, i recommend not buying hevily pregnant fish next time, buy them in the early stages or when they aren't carrying at all so that they can adjust to their new home. stress meds will also do wonders.

 

[Tokis-Phoenix]

Cheers for the info; i was quite desperate for female guppys when i got them and all the female guppys at my lfs were pregnant; otherwise i would have gone for ones which were'nt. The tank is quite planted; the tank is about 2 and a half ft tall and is octagon shaped and practically all the bottom is planted.
I suppose they could have been stressed out but it is weird they showed symtoms and the males aern't harrassing them at all; are there any particular stress meds you could recommend me as i don't have any experience in the stress-med area?

Would you say it would be safe to buy some more female guppys soon?

 

[Kiarra]

For the one that released some fry, it is possible that one of them was breach, and she died in trying to give birth to it. This used to happen a lot in people, before medical technology got to the point where now it rarely ever happens.

I had one female die that way, and several that have gone breach but survived due to intervention.

 

[vidiots]

There are usually a few nitrates in a cycled tank unless you do large daily water changes or have just those fish in like a 200Gal tank. I would suggest that you take a water sample to your LFS and verify your measurements if nothing else to ensure that you are measuring properly. My son was getting false low readings on a nitrate test because he misunderstood and was not following the directions on the test kit exactly, he was not shaking the second bottle for a full 30seconds. You may also want to check PH and chlorine if you haven't.

You appear to understand the importance of water quality so the only reason I mentioned the above is just to double check because water quality and new fish are the two main causes of fish disease in aquariums. A quarantine tank is strongly recommended for new fish to maintain the health of your existing fish. I know that can be a major pain to do, but all of the old timers of fish keeping stress this because they have learned the hard way, not to mention they usually have old extra tanks on hand so it is easy for them. Another reason for a quarantine tank is that it is cheaper and easier to medicate a 10gal tank than a 50gal. The quarantine tank doesn't have to be fancy, just the tank and a filter. Room temp and lighting are usually sufficient unless your medication calls for raised temperature, then you might need a heater. You can even avoid cycling the quarantine tank by placing a dirty filter cartridge or gravel from your 50Gal in it.

Now that you have medicated your 50gal tank keep a very close watch on your ammonia, nitrite, and nitrate levels. Even though most medications say that they won't harm your beneficial bacteria many of them do, if they don't kill the beneficial bacteria they frequently stall their reproduction resulting in problems with the above parameters. As for the sick fish there is little you can do beyond what you have already done to make them better, they will either get better or they won't.

 

[Tokis-Phoenix]

Thank everyone for all the info/advice, i shall look into getting a quarentine tank in the mean time and double checking the results, cheers!