Tank cooling questions

[sixline]

I've been trying to improve my reef keeping in the last couple of months, and I recently installed an ApexEL controller.

My tank seems to be running much warmer than I expected. I live in an unheated apartment. Well, it has heat, but I never turn it on because I live in the city of SF where it never gets very cold or very hot.

But today for example, the temperature in my apartment ranged from 66-69 degrees Fahrenheit, but my tank temperature got up to 83.2F. I have a heater in the tank, but it is controlled by the Apex and has not gone on for the past week. So I guess my lights and pumps and the biological activity in my tank is able to raise the tank temperature by ~20F. My total system volume is 110g, and I have two Hydra 26 light fixtures, a Vectra M1 return pump, two eco techs and two other powerheads for circulation.

Is that about what is expected? A tank without a heater running at a temp that much higher than the ambient room temp?

I'd like to lower the temp by about 5 degrees and also keep it reasonable stable. These are the options I can think of:

1) Get a chiller. Ugh. I really don't want to do this one. Chillers are expensive and seem like too much of a hassle for someone living where the temperature rarely goes above 70 degrees.

2) Get a couple of fans for the sump and have them controlled by the Apex. This is a bit better, but would increase evaporation and may not cool the tank very much.

3) Set the Apex to turn off a circulation pump or two when the tank temperature gets above 79. Yes, I actually am thinking about this. I think I have a pretty good amount of flow in my tank with the big return pump and the two ecotechs. The two pumps I would turn off are only providing laminar flow. Plus I think it might be beneficial to vary the flow in the tank over time.

4) Ignore it and run my tank with a daily temp of 81-83 degrees Fahrenheit. From what I read, not really in the reasonable temperature for long term success in a reef tank, but I'm willing to be convinced otherwise.

As far as livestock I'm planning only fish, CUC, and softies. Any insights are appreciated.

 

[Crustaceon]

#2 because refilling an ato reservoir isn’t too tricky or #4 because 81-83 isn’t bad, not even for acros.

I run fans on my system that switch on at 81 degrees because otherwise it’ll hit 84 around this time of year and I feel like i’m getting close to a crash at that point even if my corals don’t show signs of stress.

 

[Tuffyyyyy]

I think option #2 is your best bet. I’m shocked that your tank is so much hotter than your ambient. Maybe you could create more surface agitation to try and cool the tank down that way?

 

[X-37B]

How big is the tank?
I have a $10 8" clipon fan in my 40 breeder sump. Tanks 120.
It will lower tank temp 4° if I leave it on 24/7.
I only run it when lights are on.
It keeps tank at 78-79°.
Without the fan it will get to 82.
Have you checked the tanks temp with a different thermometer?
I verify temp with a lab grade mercury unit.

 

[sixline]

Maybe you could create more surface agitation to try and cool the tank down that way?

Thats a good idea. Maybe if I can more strategically aim my existing powerheads, I can achieve temperature reduction through more surface exchange.

I’m shocked that your tank is so much hotter than your ambient

Yeah, this surprises me as well which is why I asked if it was normal.

Have you checked the tanks temp with a different thermometer?

Yeah, I have a Hanna digital thermometer, plus one of those analog floating types. All three give approximately the same readings.

Since I have the APEX recording temperature over time, I can experiment a bit. Another idea I had was turning down the rate on my return pump a bit. It is an Ecotech Vectra M1 and has an adjustable flow rate of up to 2000gph. When I installed it, I set it as high as I could before the drains on my tank could no longer keep up. I think that was pretty close to the full 2000gph setting. That must be generating a significant amount of heat.

 

[Auquanut]

Do you have a glass lid on the display?

 

[sixline]

Do you have a glass lid on the display?

No lid, open top.

The tank is a Red Sea Max S400 system. Or it was, until I replaced the pumps and the lighting.

 

[ScottB]

I also find the temperature differential puzzling. What lights are you running?

 

[sixline]

I also find the temperature differential puzzling. What lights are you running?

A pair of Hydra 26 LED fixtures.

 

[Bosreef]

That temp increase at those ambient temps are strange to me. What happens when its 80 in your apartment.... your gonna wann figure out where all that heats coming from im very suspect of that.

On the note of cooling as long as your apartment is cooled you will be fine with a fan pointing at the water yes this will create more evorpration but so what very little cost to cool your tank by up to 5 degrees..

I have my fan kick on at 80 over the surface of the water runs for like 20 mins to get the temp back down to 78...

 

[sixline]

That temp increase at those ambient temps are strange to me. What happens when its 80 in your apartment.... your gonna wann figure out where all that heats coming from im very suspect of that.

This sort of surprise seems very common in this thread, which is why I asked if it was normal. Tank temperature is currently at 81.4 and the lights have not even come on yet. I've noticed the lowest tank temperature is about 6am, then it rises until about 8pm and then falls.

Today, I plan on monitoring ambient temperature throughout the day, and coordinating that with the tank temperature. I think once the lights go on that will add a bit of heat, and I would Imagine everything waking up and starting to metabolize might add a little bit of heat as well.

Once I have more data from the Apex, I may start experimenting by turning a particular pump or two off for a few hours and see if/how it affects temperature.

 

[h2so4hurts]

I think you will be surprised how effective fans are. Have them turn on a couple degrees below your target temp. Have them blow across the top of your tank or sump. I have mine run 24/7 and the tank is 77-77.5 all day long. AC in the basement is set to 71. Also, switch to external pumps or switch all in water pumps to DC to cut out added heat in your system. I had a mag12 and a mag18 in my sump, 265w! and switched to two Eflux 2000 gph pumps (110w at full blast, one set to 65% so probably closer to 80w total) and temp immediately dropped 3 degrees.

Best of luck!

 

[Dr. Dendrostein]

I've been trying to improve my reef keeping in the last couple of months, and I recently installed an ApexEL controller.

My tank seems to be running much warmer than I expected. I live in an unheated apartment. Well, it has heat, but I never turn it on because I live in the city of SF where it never gets very cold or very hot.

But today for example, the temperature in my apartment ranged from 66-69 degrees Fahrenheit, but my tank temperature got up to 83.2F. I have a heater in the tank, but it is controlled by the Apex and has not gone on for the past week. So I guess my lights and pumps and the biological activity in my tank is able to raise the tank temperature by ~20F. My total system volume is 110g, and I have two Hydra 26 light fixtures, a Vectra M1 return pump, two eco techs and two other powerheads for circulation.

Is that about what is expected? A tank without a heater running at a temp that much higher than the ambient room temp?

I'd like to lower the temp by about 5 degrees and also keep it reasonable stable. These are the options I can think of:

1) Get a chiller. Ugh. I really don't want to do this one. Chillers are expensive and seem like too much of a hassle for someone living where the temperature rarely goes above 70 degrees.

2) Get a couple of fans for the sump and have them controlled by the Apex. This is a bit better, but would increase evaporation and may not cool the tank very much.

3) Set the Apex to turn off a circulation pump or two when the tank temperature gets above 79. Yes, I actually am thinking about this. I think I have a pretty good amount of flow in my tank with the big return pump and the two ecotechs. The two pumps I would turn off are only providing laminar flow. Plus I think it might be beneficial to vary the flow in the tank over time.

4) Ignore it and run my tank with a daily temp of 81-83 degrees Fahrenheit. From what I read, not really in the reasonable temperature for long term success in a reef tank, but I'm willing to be convinced otherwise.

As far as livestock I'm planning only fish, CUC, and softies. Any insights are appreciated.

Unplug heater for a few days see if it changes, if it does you might have a bad relay in the Apex or possibly the heater out of calibration to

 

[sixline]

Wow, this is getting bad. Yesterday, the tank temp slowly rose all day, then the lights wen off and it went down by only .2 degrees during the night. This morning, tank temp is already at 83.1 and the lights are not even on yet. Ambient room temp is 74.

The tank is being monitored by the APEX, and I also have a Hanna checker. My ATO comes from a rubbermaid in a dark closet and the Hanna just tested it at 72.7. The line to the tank is long, so assuming the water in there heats to room temp, the tank is being dosed with two gallons of 74 degree water each day (the amount that evaporates).

So, something mysterious is raising my tank temperature 10 or more degrees every day.

I just unplugged the heater (according to the Apex, that outlet hasn't turned on), and I reduced the flow a bit on my return pump to see if that generates less heat.

I'll probably have to get some fans for emergencies, but I'd first like to determine how it is getting so hot and eliminate that issue.

If the temperature doesn't drop significantly after the changes today, I am going to turn off two of my laminar circulation pumps and continue relying on the flow from the two eco techs and the return pump and see if that reduces temperature.

What sort of temperatures above ambient is everyone else seeing?

 

[tvan]

Where is your tank in relation to a south facing wall or window?
Where are your large appliances? ie is the wall behind your tank warmer then the rest of the room? It truly sounds like you might need better air circulation around the outside of your system. Or is there a tank heater running that you think is off?
HTH
tvan

 

[Reefer Reboot]

By chance are you running a UV filter? The heaters in my tank haven't turned on in years because of the heat generated from the UV filter.

 

[jd371]

This 20g is in my workshop that has no AC. Last summer was the first summer for this tank and on some of the hotter days the tank reached just over 84 degrees. The coral and fish were fine. I do have a fan over the tank that kicks on when it reaches 80 degrees and this year I'm adding another one over the sump to help.

 

[piranhaman00]

My heaters never turn on in my 180, I use fans to cool in sump. You will be surprised how much that helps.

 

[amiromail]

I also have a Max S400, and was having difficulty keeping my temp under 81F. Then, I took out the sicce recirculation pumps from the back to clean them out and noticed how hot they felt. I never put them back in the tank and temp has been great since.