Is My Heater Too Powerful?

[miss_rawr]

I have a 92 liter tank (24 U.S. gallons, 20 uk gallons) and i ordered a 100w heater, when it arrived there was a note saying that the store was out of 100w and had instead given me a 200w.

Will this be a too powerful a heater for my tank?
thanks for any help

 

[oscars r ace]

should be ok, i have a 100w in my 25ltr tank, a 150w in my 64 so i'd say should be ok, just make sure you have a thermomiter in the tank

 

[miss_rawr]

should be ok, i have a 100w in my 25ltr tank, a 150w in my 64 so i'd say should be ok, just make sure you have a thermomiter in the tank

thanks a lot

 

[keenonfish]

Can't remember the formula now for calculating ideal heater size but there is a good reason to go with maximum heater size - if it fails and sticks on then it is less likely to raise water temperature significantly above maximum, or at least it would take long enough that hopefully it would be noticed before your fish suffered. Of course the best system is to employ x2 underpowered heaters which pretty much eliminates this problem all together.

However I have recently noticed some heaters have separate overheat stats built in so if you have got something similar chances are very very unlikely to boil your fish regardless of heater size.

 

[OldMan47]

A typical good value for a heater is 5 watts for each US gallon. That would be about 1.25 watts per litre. The 200W heater will work fine in a small tank but there is a concern there. If, for some reason, the heater sticks in the the on condition, it will quickly overheat a small tank rather than the slower rise you might see with a proper sized heater. In general, the larger heaters are more expensive, so in terms of value for your money you have done fine.

 

[miss_rawr]

thanks a lot for alll your help and advice

 

[waterdrop]

A typical good value for a heater is 5 watts for each US gallon. That would be about 1.25 watts per litre. The 200W heater will work fine in a small tank but there is a concern there. If, for some reason, the heater sticks in the the on condition, it will quickly overheat a small tank rather than the slower rise you might see with a proper sized heater. In general, the larger heaters are more expensive, so in terms of value for your money you have done fine.

I tend to be like you OM47, remembering this concern having always been important. Since this subject has come back up, I wonder if you or any other members have any new thoughts to make about the evolution (or not) of our typical aquarium heaters. In some of the discussions there's been the feeling expressed that years ago the thermostat mechanisms used to stick more (I think they were often the bimetalic metal strips where the different metals bend differently in response to temperature changes, right?) There's a tendency, without hard information, for us to assume designs have improved over the years, but maybe they've not really, I have no idea. Perhaps there are now tiny semiconductor temp sensors that are affordable to the designers, don' know! Only info I've seen are comments in some of the TFF threads on this that there are fewer reports of "heaters stuck in the on position and cooking the fish" than there used to be 30 years ago or so.

~~waterdrop~~

 

[raptorrex]

A typical good value for a heater is 5 watts for each US gallon. That would be about 1.25 watts per litre. The 200W heater will work fine in a small tank but there is a concern there. If, for some reason, the heater sticks in the the on condition, it will quickly overheat a small tank rather than the slower rise you might see with a proper sized heater. In general, the larger heaters are more expensive, so in terms of value for your money you have done fine.

I tend to be like you OM47, remembering this concern having always been important. Since this subject has come back up, I wonder if you or any other members have any new thoughts to make about the evolution (or not) of our typical aquarium heaters. In some of the discussions there's been the feeling expressed that years ago the thermostat mechanisms used to stick more (I think they were often the bimetalic metal strips where the different metals bend differently in response to temperature changes, right?) There's a tendency, without hard information, for us to assume designs have improved over the years, but maybe they've not really, I have no idea. Perhaps there are now tiny semiconductor temp sensors that are affordable to the designers, don' know! Only info I've seen are comments in some of the TFF threads on this that there are fewer reports of "heaters stuck in the on position and cooking the fish" than there used to be 30 years ago or so.

~~waterdrop~~

it would be interesting to find out. you still see a lot of comments on just this sticking problem.

 

[keenonfish]

A typical good value for a heater is 5 watts for each US gallon. That would be about 1.25 watts per litre. The 200W heater will work fine in a small tank but there is a concern there. If, for some reason, the heater sticks in the the on condition, it will quickly overheat a small tank rather than the slower rise you might see with a proper sized heater. In general, the larger heaters are more expensive, so in terms of value for your money you have done fine.

I tend to be like you OM47, remembering this concern having always been important. Since this subject has come back up, I wonder if you or any other members have any new thoughts to make about the evolution (or not) of our typical aquarium heaters. In some of the discussions there's been the feeling expressed that years ago the thermostat mechanisms used to stick more (I think they were often the bimetalic metal strips where the different metals bend differently in response to temperature changes, right?) There's a tendency, without hard information, for us to assume designs have improved over the years, but maybe they've not really, I have no idea. Perhaps there are now tiny semiconductor temp sensors that are affordable to the designers, don' know! Only info I've seen are comments in some of the TFF threads on this that there are fewer reports of "heaters stuck in the on position and cooking the fish" than there used to be 30 years ago or so.

~~waterdrop~~

I have said many times heaters are seriously lagging in the technology front and it is, I think down to marketing and cost per unit. A bimetal strip is easy to produce and costs nothing and is a proven design, in so much the fact there isn't really a demand from end users to update or improve upon the current design.
Simple custom micros have been available since the dawn of time now but have only really become cheap enough in the last few years I guess to make manufacturers look at this. Also dedicated digital temperature sensor i.c.'s can be purchased even at hobby stores for next to nothing. Trouble is the manufacturers have got to go to the expense and effort of R&D which they won't bother with unless they have to.
However, I recently saw a heater with digital control AND a safety redundant over heat stat (possibly the bimetalic bit lol) for sale and I am sure is was someone like interpet. I guess they will sell these as the upmarket ones and keep the simple technology going as a more basic product.