Sudden death - entire tank. Thoughts?

[kfish]

A couple days ago, I awoke to find that every single fish in my 10 gallon tank had died during the night. I had about 13 small fish and 3 shrimp in the tank, which was started in January. Up until this point, I have only had a few fish die, the last of which was at least a couple of months ago. The fish showed no visible signs of illness prior to their deaths.

My tank was planted. The fish that died included 2 cherry barbs, a fancy guppy, 6 neon tetras, a siamese algae eater, 3 shrimp, and 3 other tetras (black stripes and red noses).

I change my filter cartridge every 4 to 6 weeks and change about 25% of the water every 2 weeks.

The evening before my fish died, I replaced my heater. The temperature in the morning read the same as it has been over the past several months and felt normal to my touch.

Could the new heater have shorted? Other ideas? Changes that can occur suddenly in the water composition?

Now, a couple days later I notice that my plants look to be dying. Could this be related to water problems that killed my fish? Or is it lack of CO2 in the tank because there are no fish left?

Appreciate any thoughts the community may have. I'm hesitate to give it another go after this experience.

 

[fishfanatic]

I am so sorry to hear that. Don't give up! I don't know what went wrong, it sounds like to me it was a heater problem but then that doesn't explain the dieing plants... sorry I am no help

 

[eco23]

I'm sorry about your fish, but I'm glad you found us on the site. First and foremost, ignore the instructions on your box of filter cartridges. Monthly replacement is not only unnecessary, but is detrimental to your fish. The vast majority of your beneficial bacteria which converts the waste your fish produce live in the filter media. By replacing it monthly you instantly lose a giant portion of your bio-filter and it can cause ammonia and nitrIte spikes in your water which is very hard on your fish. During weekly water changes, simply swish your filters around in water you have removed from your tank to clean the debris off that it has collected...never replace them until they are literally falling apart. The recommendations by the pet stores and manufactures is a sad part of fish keeping because it is designed to make money without taking the wellbeing of your fish into consideration :-(

Do you have a quality liquid test kit? Do you know your full water parameters (ammonia, nitrIte, nitrAte, pH)?

 

[kfish]

Thank you for the advice. Unfortunately, I don't have a liquid test kit and don't know the full water parameters.

 

[eco23]

Thank you for the advice. Unfortunately, I don't have a liquid test kit and don't know the full water parameters.

I do hope you continue with the hobby. One of the things that are pretty much necessary for fish keeping is a quality test kit. Almost all of us on the site recommend the API Master test kit. It is a liquid kit that is very accurate and tells you everything you need to know. Don't trust strips...you might as well be guessing what the levels are.

Since the tank is empty and I believe the bio-filter is very damaged, it may be a good idea to do a fishless cycle to get your tank back into shape to add more fish and keep them healthy. There is a link in my signature I invite you to check out. It has all the info you need about cycling, as well as an FAQ about switching media.

It would also be important to do a lot of research on the fish you plan on adding. Stocking is not my expertise, but for a 10 gallon tank it seems very overstocked which would have greatly contributed to the problem.

A tank has to be empty to do a fishless cycle, so if you still have shrimp or other inverts in the tank, it would be necessary to temporarily rehome them. Feel free to ask any questions you run across

 

[jcolon]

I'm sorry about your fish, but I'm glad you found us on the site. First and foremost, ignore the instructions on your box of filter cartridges. Monthly replacement is not only unnecessary, but is detrimental to your fish. The vast majority of your beneficial bacteria which converts the waste your fish produce live in the filter media. By replacing it monthly you instantly lose a giant portion of your bio-filter and it can cause ammonia and nitrIte spikes in your water which is very hard on your fish. During weekly water changes, simply swish your filters around in water you have removed from your tank to clean the debris off that it has collected...never replace them until they are literally falling apart. The recommendations by the pet stores and manufactures is a sad part of fish keeping because it is designed to make money without taking the wellbeing of your fish into consideration

Sorry to hear about your fish. I have to complete agree with eco23 ... So your back to square one on cycling. Only replace when it's falling apart and then use the older cartridges to seed the newer one. Keep at it ... don't give up and consider a fishless cycle since your practically starting over.

 

[robby]

When I replace my filter, I empty the charcoal out of the old one and stick the old filtermedia in the HOB filter. Helps to speed up or even avoid the minicycle completely.

 

[eco23]

When I replace my filter, I empty the charcoal out of the old one and stick the old filtermedia in the HOB filter. Helps to speed up or even avoid the minicycle completely.

Agreed that's a good idea. You can also buy rolled up sheets of filter media that don't have the carbon in them. It is much cheaper, and carbon is only necessary for specific situations like removing medicine or color from the water column. In general, carbon is just a marketing tool designed to have you keep returning to the store and buying unnecessary filter materials.

Just because your filter has slots for cartridges does not mean you have to use them. The sheets can be cut to size with scissors and placed in the same location. Depending on your filter, you can also sometime fit a mesh bag of ceramic bio media into your filter to harbor your beneficial bacteria. Ceramics (like Fluval Bio-max) absolutely never need to be replaced and will harbor a good portion of your bacteria.

Another good idea is to always seed a new filter before replacing the old. When your filter is nearing the end of it's use, jam a new piece in front of it and leave it I'm for a couple weeks to seed it with the BB, that way when the old one is removed you already have a new one seeded and ready to take over.

I do believe you fish most likely succumbed to ammo / no2 poisoning due to monthly cartridge replacement (thanks to the recommendations from the makers), and in fact, if you've been replacing them monthly, it's possible the tank never fully cycled at all. That's one of the reasons a good test kit is so vital.

 

[kfish]

Thank you all for the comments.

If the filter cartridge is to blame, what I find strange is that it has been about a month since I last changed the cartridge. It seems that the deaths would have occurred closer to the last change, but perhaps that isn't good logic.

I had been noticing a fairly strong smell coming off my tank when I removed the lid. I didn't think much of it before, but now I wonder if it was related to ammonia build up. Does ammonia build up tend to produce an odor?

 

[eco23]

Thank you all for the comments.

If the filter cartridge is to blame, what I find strange is that it has been about a month since I last changed the cartridge. It seems that the deaths would have occurred closer to the last change, but perhaps that isn't good logic.

I had been noticing a fairly strong smell coming off my tank when I removed the lid. I didn't think much of it before, but now I wonder if it was related to ammonia build up. Does ammonia build up tend to produce an odor?

Of course I can't be 100% certain an ammo spike is to blame without accurate test results, but it takes time for ammonia to build up and spike, and it takes time for the ammo and no2 to cause serious damage to your fish.

Were there any signs like the fish breathing rapidly or gasping at the surface for air? Any indications of acting lethargic or red on their gills?

There are of course endless possibilities ranging from ammo, to some cleaning chemical making it's way into the tank. Did you do a water change recently, and if so did you remember to dechlorinate the water?

What type of odor were you noticing?

If you do continue fish keeping, and I hope you do, it would be worth running out very soon and testing the water still in the tank to discover what the issue could have been.