Hi everyone. I am a 4th grade teacher, and in past years had (2) 10 gallon tanks in my room for guppies. The kids love seeing the complete cycle of life. This year, I used a grant to get a 40 gallon tank for my room. I got everything ready to go and started a fishless cycle. Once that was finished, we added our fish. Everything was going well. We had new babies, pregnant females and no deaths. Then, over the weekend a few weeks later, every fish died. Friday they were fine, monday dead as a doornail. I thought maybe the tank got too cold (it was our first cold weekend), but the temp read 76. I also used my api test kit to check the water. All levels were normal. I drained the tank and then filled it again. Used water conditioner to treat it. We added some more guppies (young and mature). Over the next few days, most of the mature, and even a few young ones died. I checked the water again...normal. So I did a 60% change, treated the water and got some more. I had them for 2 days and already two new matures have died. Most of the fish (young and old) are close to the top. I've never had a die-off like this before and don't know what to do. Any suggestions?
Guppies dropping like flies
- Thread starter jdwags
- Start date
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IHaveAquariums
Aquarium Advice Freak
Hmmm, so you fully cycled it to start? Have you tested your water after letting it sit for a day? Have they shown any strange symptoms like stringy white poop? Do you have your test numbers to share and what filter do you have on the tank? Quick die off like that 2 things come to mind, 1) an ammonia or nitrite spike, or 2) columnaris
Thank you for the info! Yes, the tank was fully cycled. I checked the water after 2 days and then a week of having the first batch of fish. Everything was good. the fish seemed to be thriving and our tank was getting lots of little babies. When I came to school that Monday and saw the tank was dead, I tested the water and it was normal. I drained it all and started the whole process again. Once I could add some ammonia in the morning and my numbers were okay at the end of the day, I added batch #2. I had a about half of them kick the bucket over that weekend. Water tests were normal. Did the 60% change yesterday. Fish were alive this morning, but two more died by the end of the day. I dind't notice any odd poop. Should I try adding some aquarium salt to the tank?
I'm not sure of the filter brand, but it is a large power filter.
My numbers this afternoon were:
ph 7.4, Amm .25, Nitrite 0, Nitrate between 0 and 5
I'll try to look for any spots on them tomorrow.
Thanks again for the help!
I'm not sure of the filter brand, but it is a large power filter.
My numbers this afternoon were:
ph 7.4, Amm .25, Nitrite 0, Nitrate between 0 and 5
I'll try to look for any spots on them tomorrow.
Thanks again for the help!
JD
If you are certain that your tank is totally cycled, no apparent disease symptoms, and things were fine until a weekend break, I have a couple of ideas. My wife is a High School teacher. She advised that weekends are when the exterminator sprays the rooms, janitors polish floors, counters and shelves. Students tend to be more edgy on Fridays, one might have tampered with the tank. In short, fumes or other traces of toxins might have migrated into the tank.
I suggest upping the WC 's and maybe switching out the Guppies for a more durable species of livebearers.
Good luck. I know you have a very difficult job.
If you are certain that your tank is totally cycled, no apparent disease symptoms, and things were fine until a weekend break, I have a couple of ideas. My wife is a High School teacher. She advised that weekends are when the exterminator sprays the rooms, janitors polish floors, counters and shelves. Students tend to be more edgy on Fridays, one might have tampered with the tank. In short, fumes or other traces of toxins might have migrated into the tank.
I suggest upping the WC 's and maybe switching out the Guppies for a more durable species of livebearers.
Good luck. I know you have a very difficult job.
I thought about that too. I am at a small rural school and there is no one here on the weekends. I have a really good group this year too. I thought about tampering, but the kids were so invested in the fish that it would be hard to think that one of them did anything (although nothing is impossible!). As an update, I came in this morning and the water is totally cloudy. I checked the water and all of my levels are okay. Maybe it was the Tetra easybalance that I added before leaving yeasterday?
Since you have been changing a lot of water, probably some type of water chemistry imbalance, resulting in a harmless bacterial or algae bloom. Likely a good sign that things are on their way to getting back to normal. The cloudiness will clear up on its own in a couple of weeks when things level out.
Angellove78
Aquarium Advice Addict
My guess would be ammonia if you did a 60% water change before you tested the water. Chances are your ammonia was higher and killed off the weak ones. Signs of ammonia are showing when fish are at the top trying. I'd do another 25% water change and get the rest of the ammonia out in case it wants to rise again. And try not to over feed.
Angellove78
Aquarium Advice Addict
My point on this is on your test readings You still have ammonia in your tank at .25.
Angellove78
Aquarium Advice Addict
And you should not be adding ammonia to the tank once the fish are in it. I reread this again to see if I could catch something. If your adding the ammonia as if you were cycling the tank,when it's already cycled, you'll kill your fish. Toxic! The fish will do the rest at this point. Just keep ammonia out!
Thanks again everyone. I'll try to do a 25% change at lunch today and treat the water with the usual Stress Coat+. The good thing is that it is giving the kids a real-life lesson on problem solving and asking for help. The bad thing is that it is totally frustrating and our fish are dying. I'll keep you all in the loop with what I find on Monday.
I should clarify...
Used fishless cycle in October. Once I could add some ammonia to the tank and it neutralized within a few hours I decided it was time to add fish.
Added fish in late October after the fishless cycle was done. No more added ammonia.
Tank did well and fish thrived until Dec. All fish died in one weekend.
Drained tank, added new treated water, ran fishless cycle again. I really didn't need to though b/c the bacteria in the filter took care of everything. Just wanted to make sure that ammonia was being converted quickly before adding batch #2.
Tested water and added batch #2.
1/2 of the fish died that weekend. Tested water again...normal.
Did a 20% change and let it go at that since half of the fish were still alive.
No more died, but they were near the top.
That takes us up to this week. We added 6 adults to the tank. All the fish stayed near the top so I did a 60% change.
Everything was okay when I tested it last night. The Ammonia test had the slightest hint of green.
Ammonia was not added while fish were in the tank.
I'll try a 25% change and test it again.
Thanks again everyone!
Used fishless cycle in October. Once I could add some ammonia to the tank and it neutralized within a few hours I decided it was time to add fish.
Added fish in late October after the fishless cycle was done. No more added ammonia.
Tank did well and fish thrived until Dec. All fish died in one weekend.
Drained tank, added new treated water, ran fishless cycle again. I really didn't need to though b/c the bacteria in the filter took care of everything. Just wanted to make sure that ammonia was being converted quickly before adding batch #2.
Tested water and added batch #2.
1/2 of the fish died that weekend. Tested water again...normal.
Did a 20% change and let it go at that since half of the fish were still alive.
No more died, but they were near the top.
That takes us up to this week. We added 6 adults to the tank. All the fish stayed near the top so I did a 60% change.
Everything was okay when I tested it last night. The Ammonia test had the slightest hint of green.
Ammonia was not added while fish were in the tank.
I'll try a 25% change and test it again.
Thanks again everyone!
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