New tank build and wondering if chiller is needed

02tts

New member
Hi all, so I've been out of thew hobby for a good 10 years and now looking to get back in; however; I haven't made up my mind on the size of the tank. I have a custom made gorgeous stand and canopy that I held on to for when I decided to re-enter the hobby but because it's already built it limits me to a 240G long or 300G tall tank, which is fine but I wouldn't mind something wider than 24", say something like a 36"-50" which could range in the 370G-500G size (depending on the length of course). That said the question is whether there is a rule of thumb or thought as to when a chiller might be needed. Where the tank would go light/heat is not a problem, so it would be determined more by room temperature which is kept at a constant 75 during the day and 73-74 at night. It would be on the first floor. When I did this last time I had a problem with tank temperatures reaching 83-85 which would cause all kinds of issues so I had to end up getting a chiller. However; this time around I would like to avoid it at all costs, don't care for the maintenance, extra heat it introduces into the room/house and extremely loud noise they create- I know it's all relative but to me it's loud.

Back then I had MH lights, then switches to T5's which made things a little better but now with the use of LED's I have to think the heat introduced into the tank is even less, especially with more energy efficient pumps like the DC pumps. I envision there would be (1) or (2) DC return pumps, a DC skimmer pump and (2) or (3) pumps to circulate the water. This will most likely be a fowlr tank rather than a reef tank - I like many of the fish I can't mix with corals and such.

Given the size of a 240, 300 or 500 setup, do you feel a chiller would be needed? I live if S.Fla but that's irrelevant when the inside room temperature is kept at a constant, but needless to say I won't be needing a heater.

The bottom cabinet will be kept closed and the top canopy is about almost 40" high so heat would't be pressed down into the water and would have room to escape. The top of the canopy has large holes drilled for air to escape and can be equipped with fans, maybe alternating them on one side sucking air out and another pumping room air in so as to cool through evaporation. The other thought might be to put a fan on the sump but I'm not sure how effective that would be?

Because of where the tank would go, which is in the middle of a room, there is no ability to setup an auto top-off so evaporation rate is a little concern especially if setting up fans to blow air in.

Based on the above, is there any thoughts regarding anything else that I can do to cool down the tank without having to use a chiller...is there a rule of thu, that says once you pass the 300G you need to include a chiller....and any thoughts to a daily rate of evaporation on a tank that size, last but not least, would it be easier to naturally keep the 500G cooler or the 240G cooler? Wondering if the larger volume of water makes it easier for the tank to be more stable?

Thanks in advance!
 
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Ive never personally had a large tank as my biggest was a 75 but the rule of thumb I was taught by people that had large tanks is anything over 180 gal you need to plan on cooling it off... You would think that the tank size shouldnt mean anything but what you have to take into consideration is the larger the tank means you will have a lot more pumps running which produces heat. Also there is a matter of just the bacteria in the tank causes a slight amount of heat the same way a compost pile creates heat by bacteria die off and such. I will concur that led's create a minimal heat issue but there will be larger factors at play in a tank that large. As far as tank size goes, you should look at the marineland 300DD. Its 72 x 36 x 27. I plan on upgrading to a 200DD in a couple months once we get situated in a permanent home. that tank is 48 x 36 x 27. They both have a great footprint.
 
I have never run a chiller however I had my system open for a bit with the LEDs on the legs due to the canopy door being damaged in shipping. During that time I was topping the water off myself and never had an issue with maintaining the temp. Once the canopy went on the system the temp went up higher than I wanted.

Do you have any intention on running a UV? Only asking because I know my water runs out of there pretty warm; thus, acting as a point of heat that often is not considered.

I have no desire to run a chiller so my solution is to let the cabinet open in the late evening and through the night to allow cooler air to replace the warmer air that is trapped. It has worked and has caused no issues to this point.
 
Heat from LEDS is negligible. I had MH and occasionally had issues; now that I've got LEDs, it's rock-steady where I set it. I'd invest the chiller money in good LEDs.
 
I do not plan on running a UV light. They're great and I did last time but the amount of heat it creates just doesn't work for me. I was able to successfully keep the last tank wit it turned off. Although I'll admit, the water was much clearer with it on and had no algae problems.

Catch 22 I guess.

What size is your tank?
 
I have a 150 gallon tank and fully believe if it was not for the UV my water would not run too high even when the lights are on. My tank only has about a half degree temp change over the course of the day and leaving the cabinet open for a bit helps remove most of that swing (and I leave the lights on for the rap up and ramp down then followed by moon lights so they are on for a long time each day).
 
BTW---they do now make canopy fan kits, 4-5 fans in a little strip, that can cool a tank considerably.
 
I'll tell ya, we had a 125 Mixed Reef and wished there was a chiller. For about 7 years we depended on the house AC to keep things cool in the summer. The hottest day of the year it gave out. System got to 90 when I wasn't home lost a lot. The Reef was never the same.
 
I'll tell ya, we had a 125 Mixed Reef and wished there was a chiller. For about 7 years we depended on the house AC to keep things cool in the summer. The hottest day of the year it gave out. System got to 90 when I wasn't home lost a lot. The Reef was never the same.

What kind of lights are you running? I'm in stl as well but only been set up since late September. Just wondering how this summer will be.
 
T-5'S Summer is brutal in St. Louis. This was back in 2014 July. Must of been around 100. We were prepared for power outages, but not this.
 
I live in Las Vegas, during the summer some of the rooms in my house where I had tanks got as high as 85. I had nano tanks that where harder to keep cool that my 210 fowlr. The larger the body of water the more stable the temp will be and not be affected as much from room temp. I've used chillers and found that fans worked just as well. I have fans mounted and on a temp controller, when the temp exceeds a preset temp, the fans come on and bring the temp back down. This works well here in LV because it is dry and the evaporation actually makes it nice in the house. When we have our few humid days, the temp is harder to bring down. If you live in a humid area, fans may not work for you. Also most of your newer, nicer pumps and powerheads don't produce near the heat they used to, like Eheim and Sicce just to name a couple.
 
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Eheim and sicce being good pumps compared to say a Vectra, Waveline, Panworld, Blueline?

Also, thank you for the response, this actually really helps - I think the fans will help because while it may be 90%+ relative humid outside, I am able to keep it at around 52-60% inside, I know that doesn't sound all that low but living in South Florida it's hard to get any better unless I run a dehumidifier or lower the ac even more which at some point becomes counterproductive and way too expensive. But I still think running the fans might do the trick.

Do you have the fans blowing on top or the sump ?
 
I run my tanks open top and no canopy and have them mounted above the tanks. That is very high humidity, average humidity here is around 20, we consider anything above 40 high. When its been in the 60s or above is when I found it harder to control the temp, but even with the inside temp being 84-85, my tanks still ran no higher than 81-82. I lost my a/c over 4th of July weekend last year, luckily it was cloudy that weekend and my house only got to 93, was still able to keep my tanks in the low 80s and had no ill effects. Give the fans a try before investing in a chiller, think about the power bill and the fact that the chiller puts off alot of heat. With a larger chiller it needs to be in a room or area where that heat won't cause a problem, or make the room you are in uncomfortable. Attached photo is a 30 gallon kept at 80.6 with the fans you see attached at the rear in a room that gets to 85 during the day while I'm at work. I personally have experience with the eheims and sicces, but there are many others I'm sure.
 

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Chiller is a no no, I will be devastated if I end having to worry about one. If so, it will end up going outside under a covered patio, no way I'm putting it inside the house, the noise alone would drive me nuts not to mention the large amount of heat it creates. The only good thing about a chiller, besides lowering the temp is the rate of evaporation is much much less.

As for humidity, we wish we had 40's here. One of the meany reasons no one that lives in Florida like Florida in the summer months, heat is not bad but the humidity is a killer. It could be 80-85 outside and 92-95% humidity Ina sunny day...brutal.
 
Another thought, If you are going with the canopy I would just remove the top all together, you wont see it anyway. I would think you will need an ATO, topping off everyday or a few times during the day will be a pain and not as stable. I keep a 10 gallon reservoir under my 210.
 
I was thinking about having a 20g reservoir for auto top off which should last me 10 or so days at 1-2 gallons per day of evaporation which is what I suspect.

Can you recommend a good ato system setup?
 
From my own personal experience. Tunzes are great but very expensive. I don't like JBJs, freezes up but I think these are for nanos only. Hydors are junk, how stupid is it to use a temp sensor to monitor the water level. If you don't mind no bells or whistles, check out autotopoff.com
 
Thanks, I'll take a look at the Tunze and avoid the others.

Not sure why I even bother to set a budget, I've already gone over it 5x....but as long as wife is concerned, we're on track :)
 
I'll tell ya, we had a 125 Mixed Reef and wished there was a chiller. For about 7 years we depended on the house AC to keep things cool in the summer. The hottest day of the year it gave out. System got to 90 when I wasn't home lost a lot. The Reef was never the same.

For the many years we had SW summer temps were never an issue, even when the AC was off during the summer. Hoods had internal fans, but never considered any other precautions. FYI I've never had a need for a chiller or the experience of having one. Apparently not the only solution.
 
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