How Hot Is Too Hot?

[Bender]

Ive recorded huge temperature differences here over the last 10 days. The lowest was 15c the highest 36. As you can imagine a heater is necessary to avoid the lows, but with the highs being so very high I'm wondering what temperature to set it at. I have been operating on the premise that it is the fluctuations in temperature that are most harmful to my fish, so set the thermostats at 29-30 degrees. Unfortunately this makes it easier for the temp in the tank to reach 35 degrees when the day heats up. So,

How hot is too hot?

At what point should I be taking the tops of the tanks and directing a fan at them?

How big a temperature fluctuation is safe?

Could I stand to lower the heater temp despite the 36+ degree days?

And is it just my Purple (or my imagination) or are all HM/DT happier (read more active) when its hot?

[Callatya]

Are you measuring the temperature of the water or the outside of the glass? Sometimes those stick-on heaters can be out by a few degrees if they are in the sun.

Have you measured your heaters to be sure their thermostat is exact? Often they are out by a degree or two, so you might be inadvertently be setting it at 32*

I'd be tempted to set your heaters to 24* and see if that settles things down. Fluctuations are not great, but neither is running them at 35*. What temp do you run the tanks at over winter?

You aren't imagining things, fish (and quite a few exothermic things) move at a much faser rate when the temperatures increase. They'll eat more, move more, and generally be full of beans. While bettas can handle higher temps better than most, running them in overdrive constantly is probably not the best move.

Another issue with warmer water is that it is less able to hold gases, which means that it has less oxygen. Again, bettas can cope, but if you have other fish in there you'll want to get some ripply surface movement going on to cool the water a bit and get that exchange going.

[Bender]

The fluctuations of 15-36* are the actual in house temperatures. In the aquarium I'm measuring with an in-tank glass thermometer (hubby bought me two of those stick on ones, and I reluctantly attached them to my goldfish and HIS tank ) They usually read at 29.5* although two of the heaters are set at 28. Its only on hot days, or more precisely when we have several consecutively hot days, that the temperature spikes above 32*. Lately those days have been more frequent. We have no air-con here, and I don't think there is any insulation, so the house alternates between oven and freezer box. Even hubby's 50 litre tank has reached as high as 34 (using my thermometer), and it's heater is set at 24*. None of our tanks get any direct sunlight, so that's a blessing in the summer at least.

I bought my first betta Sebastion in spring, so haven't kept them through winter yet. She did very well at a constant 26*, but that was before we moved here.

Do you think they would cope better with a fluctuation of say 10* (24-34) than with constantly being in the thirties? I know my goldfish do ok with this, their tank got down to 18* last week, yesterday it reached 28*, today its 30*. They just eat a lot more, including their tank plants if I forget to give them a bit extra.

Forgot to add that we're only on a 6 month lease, so we'll probably get out of here before winter sets in. It's not just the fish who have problems with temperature fluctuation!

[Canfeleq]

If your house is mostly in the 30+ range I, personally would be looking for a way to cool them down a little. I try to maintain mine at 26 - 28 which can be hard when the house is sitting at 35. I have found that with variations of more than a few degrees (read 2 or 3) in a relatively short space of time leads to bacterial infections more often than not.

[Chuckie]

in terms of HOW to cool them down, try lids off (use some sort of net over the top ) and a fan over the surface to assist in heat exchange. There will be some evaporation though. On really hot days you can float ice in the tank (freeze some water in little zip lock bags so you can float it without releasing the chlorine etc).

Probably best to set the temp at around 25*C-ish because that way the tanks shouldn't get any lower than that, and the thermostat will keep the heater turned off on the warmer days anyway. The thing you really want to avoid is a big drop in temp, that leads to white spot/velvet city IME.

[Bender]

Thanks everyone!

I reset the heaters down to 25* last night, removed all the lids this morning and reconfigured my air stones and filters to create more surface water disturbance in the non -betta tanks. It reached 35* in the house about 3 hours ago, but almost all the tanks are stable at between 30-31* so I'd say that's done the trick. The only one that is warmer is Sebastions little tank. I think its because its less than 4 litres, so it heats up easier. I'm moving the boys into a new tank as soon as the silicon on the dividers has aged sufficiently, so I think I'll move her into one of theirs then.

[tlc33]

please please pleeaaaaasse forgive me if I am hijacking this thread, but, I have a similar problem. I have in tank thermometers. Over the warmer months I often get readings of 32 - 34 degrees celcius. I turn off the heaters so i guess there is overnight fluctuations. The warm weather is just starting here and today I have thermos reading at thirty degrees. What are the best ways of cooling tanks in this situation? Without causing stress through temp fluctuations. My tanks are approx 20 litres.

[Chuckie]

in terms of HOW to cool them down, try lids off (use some sort of net over the top ) and a fan over the surface to assist in heat exchange. There will be some evaporation though. On really hot days you can float ice in the tank (freeze some water in little zip lock bags so you can float it without releasing the chlorine etc).

In smaller tanks, use less ice and keep an eye on the temp.

leave the heater on in the tanks, but set at about 25* so they won't get too cool. They'll turn off automatically at temps of over 25* anyway.

[Callatya]

If you have HOB and you use ice, put the ice in the filter. It distributes the cool more evenly.

[finley]

I've always wondered about this. The ambient temperature in Thailand hovers around 32C for most of the year, only rarely dropping into the mid-20s during the day. Allowing for cooler (still warm) night time temps, the water in outdoor breeding ponds would mostly be around 30C, would it not?

I imagine that the Betta's native waters flowing from the mountains are cooler, but breeders' ponds must be pretty toasty.

Occasionally daytime temps hit 40C there too .

Finley

[Chuckie]

temps of 30* don't worry me. Even a bit higher. But little tanks fluctuate a LOT, and the problem is the night time dip.