I have a 10 Gallon Fish tank wherein I had a couple of Firemouth cichild and Walking catfish. Since the catfish and Firemouth grew, I had to give them away. I gave them away yesterday and in place added some small yellow morph. Today morning I found all the morph were lying dead. There is no other fish in the tank.
What could have caused this. The Old fish were healthy and good. I am not sure what could have happened or what have I missed. I am now planning to completely clean the whole tank and start afresh. After this incident, am a little scared to add new fish. What fish can I add to the tank and what should be done to avoid such incidents.
How many yellow morph did you add? If all of them were dead around the same time, it could mean they were not able to adapt to your water. The water hardness, PH, temperature etc. might be to blame.
Did you acclimate them slowly to give them time to adapt when you introduce them to the fish tank? This is extremely important every time you introduce new fish to the aquarium. Large difference in any of the 3 (water hardness, PH, temperature) can quickly shock and even kill them if you did not give them time to adapt.
When we add new fish to an aquarium, we need to first let the plastic bag sit in the fish tank water to allow the water temperature to be the same first. Then we add some of the water from the fish tank to the plastic bag. Wait 15 minutes or so, then add some more. If the plastic bag is too full, then dump some of the water before add a little more from the fish tank. (Do not dump the water from the plastic bag into the fish tank). Just repeat the process every 15 minutes. Until the water in the plastic bag is almost all from the fish tank. This is called acclimate. It can take anywhere from 1 hour to 3 hours or more. Skip this step might kill the new fish.
If your cichlid and catfish were doing fine, then the water itself was fine. However, since all of the remaining fish are dead in there. I would do large partial water change. Maybe somewhere around 70% of the water, twice in a row, or just one 90% change.
No need to take everything down, as it will crash the aquarium nitrogen cycle.
On a side note, do not be discouraged. You might also want to add new fish within a day or two. As there is no more source of ammonia, the aquarium nitrogen cycle will slowly crash on its own even if you do nothing. The new fish will keep the aquarium nitrogen cycle going.
Thanks for all the inputs. As far as acclimation is concerned, I usually let the bag float in the tank for around 20 minutes. And then put the fish in the tank along with the water in the plastic bag.
As you said, I will try to keep the tank running till I add new fish. I will do a vacuuming of the gravel and replace the tank with a 90% water change before looking to add fish to it.
Can you suggest what fish can be added to the tank.
You only allowed the water temperature to be similar. You did not let the fish to get used to the water hardness, PH, etc.
Make sure follow the true acclimate instruction. To slowly replace the water in the plastic bag with the water from the fish tank every 15 minutes or so, until all of the water in the plastic bag is from the fish tank. Add no more than 25% each time.
When you dump the water from the plastic bag, throw it away. Do not dump the water into the fish tank as the water from fish stores might have parasites and diseases.
For a 10-gallon fish tank, you can get any small tropical fish. I personally like small sized schooling fish such as Tetra. Make sure get a group of minimum 6 if you go for schooling fish. They do better in larger groups.
It is definitely due to incorrect fish acclimation.
Water temperature is only a part of the problem. Most fish shop employees will only tell you this part. After the fish get used to the water temperature, they still have to go through the water PH, hardness, and in some case nitrate concentration. New fish must adapt to all of the above before being released into the fish tank. Or you are risking killing them with shock.
