Temperature Changes

[Metalpossum]

I've just begun migrating everything to a Juwel Rio 180 aquarium, I bought it used, equipped with a 200w Aqua One heater due to the previous owner frying the included Juwel heater (Easily done, apparently). The first night with the heater on, the temperature wouldn't budge past 23.9 degrees when set to 26 (which I prefer for the Guppies, Tetras, etc that I have). I didn't know the heater I was supplied was 200w and stopped by the pet store and picked up a 200w Juwel heater, only because I enjoy matching brands up, for OCD reasons.

Upon discovering the Aqua One heater was 200w, I decided to use both heaters, one at each end of the tank. My room isn't warm during the winter, getting especially cold after I turn my own heater off before bed. (Which could be the beginning of my problem).

But when I woke up this morning, the temperature had dropped the 26.5 degrees it had reached last night, down to 23.9 degrees. The Aqua One heater, which is visible, has the LED off to show the thermostat is complacent (yet set to 26 degrees, and nowhere near).

Any suggestions to keep the temperature stable? Doing it cheap isn't a priority.

PS: I've been using two thermometers, one is digital and the other is mercury or spirits. Both show similar figures. I only have 3 Guppies in there, I'm going against the grain and trying some fish-in cycling, but I'll probably give my other filter a good squeeze to hurry things up a bit. The previous 38 litre tank and 50w (Aqua One) heater never had any temperature troubles.

[Ira]

But when I woke up this morning, the temperature had dropped the 26.5 degrees it had reached last night, down to 23.9 degrees. The Aqua One heater, which is visible, has the LED off to show the thermostat is complacent (yet set to 26 degrees, and nowhere near).

Set to 26 degrees according to the absolutely useless better off guessing poor accuracy scale on the side? Or 26 degrees actually measured?

Solution: Turn it up a little.

Any suggestions to keep the temperature stable? Doing it cheap isn't a priority.

If you really want it good and reliable get a temp controller. Overkill for a tiny tank with a couple guppies.

but I'll probably give my other filter a good squeeze to hurry things up a bit.

Or just swap all the media, instant cycle.

[Adrienne]

200 watt is a bit on the small side for your 180 tank as recommended is 1.5 watts per litre.

Depending on where you live will also determine how hard your heater will have to work. There is nothing wrong with having two heaters in the tank as if one should fail, the second one should back up.

Is you heater vertical - how close to the heater are your thermometers?

Some heaters need calibrating as not all read what they are set to. You can adjust your settings to get the tank where you want it. So if your thermometer shows 23.6 and your heater is not on turn it up a degree or two and keep an eye on it until the heater turns off. Then check the temperature.

Heaters generally have an accuracy of around + or - 1 degree.

I personally don't have an issue with Aqua One heaters, my back ups are Aqua One but I do prefer the Eheim heaters (these must be calibrated).

By the way its not that easy to fry a heater - either leaving it turned on while draining the tank or taking it out of the water while heating are about the only ways.

[Metalpossum]

Solution: Turn it up a little.

Or just swap all the media, instant cycle.

It reaches 26 degrees fine, actually reaches 26.5, but overnight since it is winter, the temperature drops to 23 degrees or so. The thermostat in the heater doesn't seem to care, because it doesn't switch back on unless I set the temperature higher, which I find odd. I suspect my T5 lighting (45w) is also part of the temperature issue.

My current solution for this is probably Eheim Jager heaters, I've been doing plenty of reading about and somebody noted that the Jager kept consistent temperatures, whereas his Juwel did not.

I shouldn't need it, especially with two heaters in use, but perhaps 300 watts instead? My other idea is to neatly use some foam on the back of the tank for minor insulation, if anything it'll probably only help the power bill by 10 cents or so.

As for swapping the media, my last tank didn't really have "media", it was a "toy" fish tank with overhead filter. I think it had carbon pellets built into the filter trays and some coarse sponge.

[Metalpossum]

200 watt is a bit on the small side for your 180 tank as recommended is 1.5 watts per litre.

Depending on where you live will also determine how hard your heater will have to work. There is nothing wrong with having two heaters in the tank as if one should fail, the second one should back up.

Is you heater vertical - how close to the heater are your thermometers?

Some heaters need calibrating as not all read what they are set to. You can adjust your settings to get the tank where you want it. So if your thermometer shows 23.6 and your heater is not on turn it up a degree or two and keep an eye on it until the heater turns off. Then check the temperature.

Heaters generally have an accuracy of around + or - 1 degree.

I personally don't have an issue with Aqua One heaters, my back ups are Aqua One but I do prefer the Eheim heaters (these must be calibrated).

By the way its not that easy to fry a heater - either leaving it turned on while draining the tank or taking it out of the water while heating are about the only ways.

Well, before going to bed the temperature was at 26.5 degrees, with both heaters set to 26. The cold of the wintery nights here in Christchurch obviously got the better of it. That said, the heaters didn't seem to care this morning, as if the thermostats are lazy. I've got two 45w T5 tubes in place (built into the hood) and I think they're partly to blame too. I've read plenty about the Eheim heaters, and I'll probably just go and get a couple, perhaps in 300w since the price difference is minimal. I would have thought 2 x 200w heaters would be sufficient. My heaters are at the back corners, my thermometers are at the front corners. I like to keep some distance, so that I know it's a tank-wide temperature and not just localised.

[Adrienne]

Your T5 lighting will heat the tank during the day so your heaters are unlikely to come on. If they are accurate they would be on in the morning when the tank temp has dropped. Turn them up a bit.

Eheims are pretty accurate as long as you calibrate them properly.

[Metalpossum]

I've set them both to 28 degrees now, and the thermostats cut off at a measured 26.3, my lights are on too. I suppose the heaters just did need to be turned up a bit. I suspect last night's temperature was lighting related, interesting to see how it works out for me in the morning. These 3 guppies I have in there aren't complaining, they were a bit slower in the morning, but they've always been slow in the mornings.

[Metalpossum]

So, the temperature crept up to 27.3 degrees before I went to bed. I left my bedroom heater on a lower setting overnight, and the aquarium only dropped to 26.3 degrees. The tank lights were off overnight.

My last tank was a set-and-forget type affair, never gave me this much anxiety. Perhaps I'll just go sink a few dollars into a couple of Eheim Jagers, I know if I use heaters that are too big, the only problem is when the things stick on, but another 100 watts per heater only costs an extra $6 total, and that should be suitable for the wintery fluctuations in my sleepout.

I've got the tank lighting on today, but I'm at work so can't monitor it. I'm growing some Eleocharis Pervula (Dwarf Hairgrass) so I decided to risk it. It's the stock lighting system supplied by Juwel, 2 x 45w "Nature" tubes (warmer colour than the originals), so I wouldn't suspect it to be the problem.

Thanks for all the help.

[Ira]

So, the temperature crept up to 27.3 degrees before I went to bed. I left my bedroom heater on a lower setting overnight, and the aquarium only dropped to 26.3 degrees.

1°is fine.

My last tank was a set-and-forget type affair, never gave me this much anxiety.

You're giving yourself the anxiety. :nilly: :slfg:

Perhaps I'll just go sink a few dollars into a couple of Eheim Jagers, I know if I use heaters that are too big, the only problem is when the things stick on, but another 100 watts per heater only costs an extra $6 total, and that should be suitable for the wintery fluctuations in my sleepout.

Wouldn't bother now that you seem to have the heaters set right.

I've got the tank lighting on today, but I'm at work so can't monitor it. I'm growing some Eleocharis Pervula (Dwarf Hairgrass) so I decided to risk it. It's the stock lighting system supplied by Juwel, 2 x 45w "Nature" tubes (warmer colour than the originals), so I wouldn't suspect it to be the problem.

I'm not convinced there is a problem. Tank warms up a tiny bit during the day, cools a tiny bit at night. A little bit of fluctuation is not a problem, the problem appears to be you staring at the thermometer microanalyzing every 10th of a degree change. :slfg:

[Caryl]

I'm not convinced there is a problem. Tank warms up a tiny bit during the day, cools a tiny bit at night. A little bit of fluctuation is not a problem, the problem appears to be you staring at the thermometer microanalyzing every 10th of a degree change. :slfg:

:iag: . Temperature variations are normal and the temperature of the room will add to the variables. Slow drops and rises throughout a 24 hour cycle are nothing to worry about and the fish won't mind. Now you have raised the overall temperature all should be within "normal" limits.

[David R]

Buy a 300W Jager heater and an accurate digital thermometer, or even better a digital controller for your two existing heaters. Most of the thermostats in aquarium heaters [particularly cheap ones] aren't that flash, and trying to balance multiple heaters is nearly impossible. A controller will give you the ability to set the temp you desire and it will only fluctuate by 1C before the heaters come on, you won't get it much more stable than that.