100 Watt Heater

[ghent_3rd]

Can I put a 100 watt heater in a 40 litre tank??

I have a spare one and would like to use it but can you have a heater that is too big for the tank???

I don't want to fry the fish with a heater too big!!! I'm hoping that due to how they work it should be OK but would like confirmation of this!!

 

[Rooster]

There ARE NO LAWS for this.... you can have it in a tea cup if you like !!!!! so YES use it


(there WILL be some doom bringer along in a minute to counter this statement...)

 

[three-fingers]

I currently have a 200w heater in a 25l tank . But its temporary.

I think the idea was that it's not recommended because over the long run because it may make the heater more likely to stick on (cooking your fish) or less frequently - off (not too much of a problem unless the rooms freezing or it goes unnoticed for ages).

This is just because theoretically, with a smaller heater, when the temp drops .5*C below what it's set to, it will take longer to heat it up - say 5 mins for example.
However with a larger heater, when the temp drops it will take less time to heat it up again - lets say 1 min, after which the temp starts to drop again and they cycle happens faster - meaning the heater is switching between on and off far more often than usual, increasing the likelyhood it will stick in one position (which is pretty common with aquarium heaters).

Obviously the bigger the heater is and the colder the room is the worse the effect.

I would think 100w for 40l would be a safe bet though .

The recommended is 50w I believe.

 

[ghent_3rd]

Well that's good news then, saved me a few quid until I see a cheap 50 watt come along!