Heater Does Not Keep Water At A Constant Temperature!

[adh/smile]

HI guys,

I have a 29 gallon tank with one 200W Tetra heater from Walmart. I bought from Walmart because it was cheapest. I have two other 10 gallon tanks with smaller Tetra heaters. I don't know what wattage the smaller ones are, the package just said 5-15 gallon heater. I am very pleased with them as they keep the water at a steady temperature of 78 degrees Fahrenheit. I bought the 200W heater for my 29 gallon tank expecting the same results. However, this heater is not consistent. It keeps the water no cooler than 74 F., but throughout the day from morning till evening, the temperature ranges from 74 F. to sometimes just below 78 F. These temperature swings don't seem to be affecting my fish, but I'm annoyed by the inconsistency!

So a couple hours ago I decided to do a little experiment: I added one of my 10 gallon heaters (one that is no longer in current use) into my 29 gallon tank. All the Tetra heaters have red lights that turn on when the heater is heating the water. The light on the 10 gallon heater I added to my 29 gallon tank hasn't gone off since I added it into the tank. The light on the 29 gallon hasn't turned on at all, but it can't be broken because the temperature is at least at a constant-ish 74 F and my fish seem fine. I'd like the water to be at 76-78 F.

So now I'm thinking these two different sized heaters have different temperature settings. The 29 is set for around 74 F. (though it's still inconsistent and that bothers me), and the 10 is set for 78 F. because that 29 heater has not turned on since I put the 10 in there. The temperature is slowly rizing. Right now it's 75 F. Should I keep this 10 gallon heater in the big tank? Would that cause it to overwork with so much water to heat? What happens if a heater works too hard?

I'm also looking into buying a new adjustable heater. That way I can control the temperature if my fish get sick. That has happened recently and I only had these Tetra heaters and all half of my fish died. Any suggestions on what adjustable heater is best?

Thanks everyone! Sorry for the length of this thread.

 

[david1978]

I'm using linba heaters right now.

 

[techfool]

Sometimes the theromostat stops working properly. I'm currently using Newa More heaters in my tanks, made in Italy so they claim. I like them for being quite small.

 

[DarkOne]

It could also be placement. The circulation might not reach the new heater as well as the little heater.

 

[adh/smile]

It could also be placement. The circulation might not reach the new heater as well as the little heater.

The big 200W heater is right under the intake tube for my HOB filter and almost right under the waterfall of my filter. I put it there because I thought it was a good circulation place, but would the warm water just stay within that circle of up and out of the filter? Maybe I should try moving the heater away from that water movement and see if that helps.

 

[adh/smile]

david1978 and techfool, thank you both for suggesting the linba and New More heaters. I will look into those more when I have time!

 

[DarkOne]

I picked up an Aqueon Pro 150w for my 40b and liked it so much I upgraded to a 200w so I could move the 150w to my 20H (replacing a cheap Top Fin 100w heater). Both have been keeping temps within .5 deg in both tanks. I have Fluval 206 and 306 and digital thermometers. Room temps have been fluctuating about 8°F the last week or so (68° to 76°F).

 

[adh/smile]

I picked up an Aqueon Pro 150w for my 40b and liked it so much I upgraded to a 200w so I could move the 150w to my 20H (replacing a cheap Top Fin 100w heater). Both have been keeping temps within .5 deg in both tanks. I have Fluval 206 and 306 and digital thermometers. Room temps have been fluctuating about 8°F the last week or so (68° to 76°F).

Does the room temperature fluctuation affect your tank's temperature? I hadn't thought of that as a reason before now. I'll look into the Aqueon Pro. Thanks for the sharing!

 

[DarkOne]

It could if the temps go crazy like it did last weekend and your heater wattage is too low. There was a chart showing wattage vs how much higher you need the temps over room temp and the 150w was just enough for my 40B.

I originally got the 150w Pro for my 40B from the advise given here (model, not wattage). The main reason I upgraded to a 200w is because the Top Fin 100w heater I had in my 20H had moisture inside and there was a sale at my LFS on the Pros. The 150w and 200w was a buck apart so I figured I'd move the 150w to the 20H and put the 200w in the 40B.

It's made of metal so no chance of it cracking, shattering or exploding. The adjustment knob is well shaped so it's easy to turn with wet hands. There's a LED light that turns red when heating and green when temp is right. They look pretty good too.

 

[adh/smile]

It could if the temps go crazy like it did last weekend and your heater wattage is too low. There was a chart showing wattage vs how much higher you need the temps over room temp and the 150w was just enough for my 40B.

I originally got the 150w Pro for my 40B from the advise given here (model, not wattage). The main reason I upgraded to a 200w is because the Top Fin 100w heater I had in my 20H had moisture inside and there was a sale at my LFS on the Pros. The 150w and 200w was a buck apart so I figured I'd move the 150w to the 20H and put the 200w in the 40B.

It's made of metal so no chance of it cracking, shattering or exploding. The adjustment knob is well shaped so it's easy to turn with wet hands. There's a LED light that turns red when heating and green when temp is right. They look pretty good too.

The only chart I've ever seen with heater-wattage and gallons of water in a tank was a small chart on the instruction paper that came with my heaters. They say: Model HT30 is 10-30 gallons = 100W and Model HT55 is 30-60 gallons = 200W. Since I was dealing with a 29 gallon tank, I went with the HT55 22W heater. Someone else on this forum advised me to go with the larger wattage.

I love sales at pet stores, though they can be dangerous because you buy so much! LOL!

I really want one of the heaters that you have! I am kind of paranoid that my Tetra heaters will explode. I've read horror stories from people who have experienced malfunctions with their heaters and I dread that it will happen to me. The fact that your... what were they, Aqueon filters? are made of metal, AND are adjustable; that is a HUGE relief in my book! I'll keep my eye out for one in the stores!

 

[DarkOne]

I got the Aqueon Pro 150w from Amazon for $28. Pet Supplies Plus (chain store) had the Pros on sale for 50% off which ended up being $28 for the 200w ($35 on Amazon).

Looks like they dropped the price on Amazon to $28 for the 200w.