I live in south africa, cape town.
Too many hot in summer. My tank is always around 25-26'C, but now is around 29-30'C how can i make to low temp? Temp control heater?
You could also put ice in a bag in the tank to lower the temp. But then you run the risk of putting too much and making the tank too cold, and temperature swings.
the lights can also add temperature to your water if there is no air circulation between the lights and the water surface. furthermore whatever is underneath the tank can also affect the water temperature. play around with that, maybe more the lights, make more holes in the tank screens, set a fan blowing onto the top of the tank, if it makes a difference then you know whats causing the temperature increase.