Loaches Online Forum

I have, what I think is a 30 gallon tank, what size heater would be good for this tank? It's going to be a hill stream tank.

Usually you need about 5 watts per gallon. I get mine a bit bigger than that too. I think at least 150 W. That should work

Oh, and if you are not sure about the size of the tank, go on http://www.firsttankguide.net/calculator.php and type in the dimensions. If it is a 30 gallon, you can use the 150 W heater

If you are thinking of keeping sucker-bodied type hillstreams in a regularly heated home environment then you won't even need a heater.

I've kept hillstreams since 1999 and never used a heater. During the summer, keeping a tank cool enough can be the issue without air-conditioning.

My 65 gallon hillstream tank is sitting at 75 degrees F as I write. The high turnover powerheads and filters that control the tank's environment keep it warm.

Martin.

I also have found that the equipment running on the tanks will keep them at a reasonable temperature, as long as the home is kept comfortable. I do need to add a heater in the winter, though, as my house is not always kept that warm.

Yes, about 5 watts per gallon is right. On this size tank, and with such great circulation one heater is plenty. On my larger tanks (50+ gallons, 4' long) I often use 2 heaters, combined to equal about 5 watts per gallon.
The larger tanks hold their heat better, so on my 125 gallon tank I have only around 400 watts of heaters (2 @ 200 watts) and this tank stays stable, and quite warm.

It really depends on the ambient heat in your home, specific tank location and what you're actually keeping. In a 30 gallon tank in the average home a small heater-stat set in the low to mid 70's (for hillstreams) will likely seldom switch on. Therefore, all though it's in there it's not doing anything most of the time, but provides backup.
In my 125 with Discus the temperature is maintained at 85 degrees F by two 200 watt heaters.

Martin.