How long can a tank go without heat?

[Treefer32]

My return pump died. I have a spare on my water change station, however, when I hooked it up, my plumbing started leaking. My union gasket was compressed and allowing water through after disconnecting it. My bulkhead on my sump also started leaking, etc... Now, after ripping everything a part and putting a new bulkhead on. I couldn't get the new bulkhead to tighten onto the sump. (It's in a really hard to get to spot and hard to put enough force on it to tighten to the glass. (There's about a 1/8" gap between the gasket and the glass. I'm planning to get help after work today, but my skimmer, heaters, and everything else is shut down for the moment on the sump.

My display still has powerheads running and lights all running just fine. Will everything be o.k. for 4-5 hours without heat? The sump temp prob is showing a 2 degree loss of heat so far...

 

[DeniseAndy]

As long as you are not in Antarctica, you should be fine. Fargo is close to the Arctic, but not this time of year. My tank has had no heat for months. Well, it is now summer, and I use a chiller. You should be fine. You do not still have snow on the ground right????

Heehee, I am from Minnesota, so just kidding around.

 

[Fish Think Pink]

My return pump died. I have a spare on my water change station, however, when I hooked it up, my plumbing started leaking. My union gasket was compressed and allowing water through after disconnecting it. My bulkhead on my sump also started leaking, etc... Now, after ripping everything a part and putting a new bulkhead on. I couldn't get the new bulkhead to tighten onto the sump. (It's in a really hard to get to spot and hard to put enough force on it to tighten to the glass. (There's about a 1/8" gap between the gasket and the glass. I'm planning to get help after work today, but my skimmer, heaters, and everything else is shut down for the moment on the sump.

My display still has powerheads running and lights all running just fine. Will everything be o.k. for 4-5 hours without heat? The sump temp prob is showing a 2 degree loss of heat so far...

Depends room temperature - i would think since it's summer you are fine, but if your home A/C is super cold like your winter temps... OR if there is a heat wave going on and your home A/C is off... IF you need to heat/chill tank then find something clean in recycling, fill with ice or microwaved hot water, seal (tighten cap of whatever pulled from trash but clean) and drop into tank to nudge up or down... BUT likely not worth the efforts for 4-5 hours, depending tank's surrounding room temperature

 

[Treefer32]

As long as you are not in Antarctica, you should be fine. Fargo is close to the Arctic, but not this time of year. My tank has had no heat for months. Well, it is now summer, and I use a chiller. You should be fine. You do not still have snow on the ground right????

Heehee, I am from Minnesota, so just kidding around.

Ha! no, ambient temp is 71 and fish room is like 75 due to the dehumidifier. My gyres are pulling in air bubbles due to being too close to the surface right now. So, should all be good.

 

[Joe31415]

Like others said, you'll probably be fine. I suppose you could throw something over the top (cardboard, a blanket etc) to help keep the heat in, but if it were me, I'd just take the/a heater from the sump and put it in the DT. It's not like it's doing a whole lot of good down there right now anyway. Don't even have to do anything special with it. I wouldn't even 'mount' it. Just put it in the water.
Having said that, now that I think about it, if you only have one heater in the sump and you move it into the DT, I'd let it run in the sump for a half hour or so before you turn everything back on so the DT doesn't get a rush of cold water. The sump, being smaller, will lose heat a lot faster than the DT.

Even a spare undersized heater (ie, one from a QT set up) will probably be able to maintain the temp for a few hours.

 

[Biglew11]

As others said probably fine since its summer. Might be wise to have a thermometer in the tank that you can read at a glance just to spot check periodically, even when things are good.

+1 on matching sump temp to tank temp before turning pumps back on.

 

[Joe31415]

So in an odd coincidence, my power had been out for about 24 hours after posting to this thread. My tank dropped from 79ish to about 73. After a full night of no power and hearing the energy company say it would be turned on some time between the end of the day and a few days later, one thing I tried was taking a pot of water, heating it on my (gas) stove until it was about 80 and pouring it back it. That made just about no difference at all.
I ended have a whole bunch of Ryobi 40v batteries. Ryobi makes an inverter that uses those batteries and outputs 120v. I used that to run a 100w heater in the tank. Between the heater and periodicaly running a power head for a few minutes to keep the warmer water circulating, I got the tank up to 75.
I have a feeling everything probably would have survived since it was *really* hot out and my house was probably in the upper 70's during the day. But it certainly didn't hurt and it's a nice little gadget to have around, even for not reefing reasons.

Also, while the power was out I unplugged the return pump so I can let the two heaters in the sump warm the water up. Once the sump and DT were about the same temp, I turned the return pump back on.

 

[BoneDoc]

If anything Without power you’d be better with colder temps. The fish’ energy consumption would be lower. The oxygen dissolves better in colder temps. Those should compensate for the reduced aeration because of less water movements

 

[Joe31415]

If anything Without power you’d be better with colder temps. The fish’ energy consumption would be lower. The oxygen dissolves better in colder temps. Those should compensate for the reduced aeration because of less water movements

I didn't know that, but there must be a lower limit and I had no idea how long I was going to end up without power or how cold it might get. I did also have the powerhead pointed towards the surface. Just enough to get the water rippling a bit, but at the same time trying not to move to much of the heat out of the tank.

In any case, it should be noted that this is a very temporary solution. A 100W heater and a small powerhead will only run for a few hours on one of these batteries. Then you need to figure out a way to charge them back up again. Luckily, I had 3 40v batteries on hand, all charged, so I had a lot of time. But if the outage lasted any longer, my intention was just to bring them to work each day and recharge them and hope the temp swings wouldn't be a lesser evil than the tank temp falling to far.
I even considered getting a 12vdc to 120vac inverter so I could recharge the batteries from my car (or even just run the as much of the tank as I could off it), but that just seemed like a waste of gas.

I kept reminding myself that fish are shipped across the country everyday and they seem to survive well enough that it's a pretty good sized industry. Surely, mine will be okay for a day or two in slightly cooler water.

At least one thing that told me whatever I was doing was working (opened shades to let sunlight into the room, powerhead, heater) was that my euphyllias opened up and my Royal Gramma came out of wherever it hides itself at night.

 

[Tamberav]

Heat isn't a problem if your house isn't freezing cold. Just keep some sort of flow going... a battery operated airstone is fine. You can get them at bait shops and I have seen them at walmart before.

 

[Joe31415]

Heat isn't a problem if your house isn't freezing cold. Just keep some sort of flow going... a battery operated airstone is fine. You can get them at bait shops and I have seen them at walmart before.

I considered running an airstone (without the sump, I had no skimmer for aeration). But since I had the powerhead in there to move the heat around, I assumed I was fine.
And now I've got that inverter to provide 120. If it happens again, I'll probably just plug one of the MP10s into it. Specs say they're 8-18 watts.
My 'back of the envelope' math says the MP10 should be able to run for about a day on a 40v 5ah battery. The little no name one that's probably meant for a 20g tank, but does a really good job in my Brute mixing barrel should last about a week. In theory anyway, that's not taking into consideration all the inverter's circuity and the considerably amount of heat it generated. So, cut the numbers in half.
Considering I already had the batteries, the 80 bucks wasn't the worst investment.

 

[DeniseAndy]

The real worry is if the tank gets too hot or really really cold. In the 70s is fine as long as you do not fluctuate by too much. Over 3 degrees F is about max. Then stress begins, but once stable, most things will be okay.

Not so with hot temps. Things die at hot temps fast. Low temps, stress, slow down, then die. Much slower process. You should be fine.

 

[Tired]

Earlier this year, my tank wound up in the mid-high 60s for a couple days, as our power was out during a long freeze (though I had a battery backup for filter + heaters) and my room got super cold. Everything seemed okay. I don't recommend it, but I didn't have anything showing any signs of stress.

As said above, cold is much less dangerous than heat. Heat drives the oxygen out of the water, while also increasing the metabolisms of everything in the tank, and thus increasing their demand for scarcer and scarcer oxygen. Cold water slows their metabolisms, which isn't great for them, but is much more survivable.