- You only need a heater for warm water fish which is most fish
- Some fish that can do without or don’t need a heater are goldfish, guppies, and shrimp.
- A 20 watt heater is usually enough for anything up to 35 gallons
- Do not plug in the heater when it is not in water (any more than 10 sec could be dangerous)
- Put it in the water first and then plug it in.
- Leave it there for 3 hrs and then check the temperature reading on your thermometer.
- If the temp is too high then turn it down and check the temp again in a few hours.
- Most fish do well when the temp is around 28 Celsius. You can google the required temp that your fish needs and adjust accordingly.
- Never put fish in the tank until the temperature is right. Fluctuating temps can make fish sick. If can take as long as a couple days to get the temp just right.