I have a different kind of cichlid fish and I live in Lahore, Pakistan. It's summer time here and the temperature is 50°C in day time and 32°C in night.
My fish tank is about 45 Gallon and the temperature in the tank was 35°C... But I tried bringing it back to 32°C.
In the last two weeks my 6 fish died. They were big and healthy. No disease or wound. Still they are dying.
Can anyone help? :(
Having the temperature too hot will have many bad effect on your tank as you found out. Livestock, and plants will die, algae will grow crazy etc.
One thing to keep in mind about high temperature water is that it contain less oxygen than cooler water. So make sure you have a good surface agitation. You can also add and air pump to help with gas exchange.
If the situation is temporary, this doesn't seem to apply to you, there are many way to cool the water a bit. Having a cold water bottle floating in the tank, do a small water change with cooler water, and probably a lot of other things. In you case since the situation is not temporary, I thing your best bet would be to invest in an appropriately size chiller for your aquarium. I'm sure there are other options less costly than a commercial chiller. By searching quickly I found this video here about a cheap diy solution. It might be worth a shot before investing big money on a chiller.
Anyway I hope this gave you some idea and that your fish will stop dying
Can you explain what type of cichlids are in the tank and how the tank is setup? 35C is hot, but many cichlids can handle this temperature if they have adequate oxygen.
I suspect your fish are actually suffocating and not dying specifically because of the temperature. At this temperature, water has almost no ability to hold oxygen. Make sure there is ample surface agitation, limit stocking, run a good airstone, and do not use CO2. This is almost compulsory keeping tanks even at 32C.
If your humidity is low, you can use a fan across the water surface which will cool the tank by evaporation. This is actually very effective if there is enough airflow, but the humidity around the tank needs to be low, and it will require you to frequently top off the tank due to evaporative losses. If you live in a very humid area, this is usually a waste of time because you cannot get enough evaporation needed to effectively remove heat from the water.
Other than evaporative cooling, you're basically at getting a commercial chiller. For this size tank there's not really any other option that is reasonably effective at keeping it cool.
