guppy fin problem - I don't think it's rot

[Jharvey]

Hi all... I'm setting up and cycling my friend's 5-gallon tank for her. I added some of my filter media to her filter as well as about 2.5 gallons of water from my established 10-gallon tank. (Per the advice of the lfs - I won't do this again). My established tank tested 0ppm for ammonia and nitrites but 5ppm for nitrates. I had only ever read that nitrates are a problem at concentrations above 40ppm (some places say much more), so I wasn't worried about that.

I brought brought three male, fancy guppies home in the late afternoon. Water has been at 74-76 deg. F; 7.6ish pH; still 0 for ammonia and nitrites and 5ppm nitrates. I acclimated them to the tank water by leaving them in the bag (which had maybe 3 cups of water), in the tank, and adding about 1/4C of tank water to the bag every 10 minutes or more. After over two hours, I netted them out and put them in the tank and discarded their original water.

They seemed fine the next morning. Numbers were the same. I did a pwc of about 1 quart dechlorinated water (treated with Seachem Prime). Then I left for work. When I got home 6 hours later, one of them was dead on the bottom I took water samples for testing and then did about a 25% water change. The numbers had stayed stable - 0 ammonia and nitrites, 5ppm for nitrates.

Any ideas about why he died? The pet store said having ANY amount of nitrates invalidates their warranty... I didn't realize 5ppm would be bad. Has any one else heard that?

Here's my bigger question: Should I be worried about the other two? They seem very active but it almost seems like (for one of them) his tail fin is kind of shrinking or shriveling a little. I've read about tail rot and it doesn't seem like that - no white spots or anything. It just seems a little more compressed, kind of like a partially-folded paper fan instead of being fully fanned out. Any ideas? I could be imagining things because now I'm paranoid about killing the other two (see pic below - it's the yellow/black one I'm a little worried about).

And should I wait to add another third? I don't want to stress them by having too small of a school but I also want to be cautious.

(other details: gravel bottom, three plants, 5-watt pre-set heater, low surface agitation from the filter - which came with the aquarium: "mini bow 5")

Thank you!

 

[jessipanda]

It seems like he is clamping his fins which could indicate many things. 2 hours to acclimate is a very long time, especially since they produce waste in the bag. I never acclimate in a bag for more than 30 mins because of the possiblility of ammonia build up. That may habe caused some issues and would explain the one death and the one with clamped fins. Simple stress or genetically weak fish could also explain what's going on, but it's harder to tell with guppies since they are so sensitive and prone to illness. Try adding some epsom salt. I'm not sure how much to add for a 5g, but you could look online. If the tank only houses the 2 guppies, I'd start with 1 tablespoon, disolved in a cup of tank water, and added slowly over the course of a few hours. Guppies actually like a bit of salinity anyways and it helps their immune systems as well as stress levels.

Keep an eye on the flow of the tank. They don't like high flow because of their long fins. It makes it hard for them to swim

Also, guppies don't need schools. They do just fine as single fish. Just keep it to either only males or at least 2 females for each male. With a 5 gallon, you're better off sticking with just the two males.

Good luck.


Edit: Oh! And the 5ppm of nitrate is just fine. Wouldn't kill them. Just try to keep it as low as possible, at least below 20ppm for them.

 

[Jharvey]

Thanks so much for all of the info. I really appreciate it. Glad to have a name for what he is doing with his fins and the (obvious in hindsight) note about not acclimating for too long a period in the bag.

They seem to be doing alright so I'll just keep testing and keeping an eye on everything - hopefully I've taken care of any remaining stressors and he can settle into his new home.