Summer is here, lets talk heat control

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Ichthys

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OK with the return of 80 degree weather many of us are back to scrambling to find a way to keep our water temps down. There are so many options and pros and cons to each, I thought I would start a thread for people to discuss what has and hasn’t worked for them. I will list the ones I can think of, as well as some of my own thoughts on each, and lastly a “new?” idea I came up with while trying to fall asleep at 1am last night.

The problem: Water temps rising cause tank livestock to suffer. Heat is introduced to the tank via lighting, MH being the worst culprit, pumps, and power heads, even my Vortech with external motor still imparts heat to the tank. Add 80 degree and above room temperatures and the water temp starts to climb.

Solutions, (in no particular order). When referring to ideas I am imagining a 90 Gal tank.

Chillers; there are either the drop in coil kind or the inline type. Pros; They work well and are less fuss. Cons; price, they are quite expensive, maybe noise? Durability? Not really sure as I have never had the luxury of an extra 600 bucks in my pocket to buy one. I have also heard of people making home made chillers with a dorm fridge or some such, but heat transfer laws suggest this is less than practical

Fans: Blowing air across the water surface to bring temp down. Pros; relatively cheap, whether you use a desk fan type or perhaps some 180mm PC fans, you can do this for the cost of a movie night with the family. Cons; I believe that the reason fans work has got something to do with the evaporative process, hence adding a 75 CFM fan to the top of your tank will probably increase your ATO duty. Second, NOISE, my tank is in the bedroom and nothing spells love in the bedroom like the sound of a 747 landing next to your bed. Third, durability, I use the cheap 10 dollar clip on fans and after 6 months they are toast. Did I mention noise?

Room or central Air Conditioning. Yep, just keep the whole room (or house) at a nice 65 degrees and that solves most heat problems, unless of course you have 2000 watts of MH, then you may need to drop the AC to 55 and put on a sweater. Pros; the wife will love you, no better way to get your wife in the bedroom than to have it be the only room of the house that is 65 when its 90 outside. Cons; expensive, both for a portable unit, a minisplit, or whole house AC, not to mention the AC to run it. Also the portable units are unsightly.

Reduce the heat you introduce to the tank, ie change to LED lighting. This would be my preferred solution but enough LED to grow my corals and get the look I want on my 90 is still above my budget. I am hoping that as more reefers buy LED’s we will see a boost in the second hand chiller market as people discover they don’t need their chiller anymore after switching to LED. Pros, LED are cool, both temperaturewise and the geek factor. Cons; price…

I have also heard of people using bags of ice or other simple ways of trying to bring down temps on a tight budget. So, what have you tried, what works what doesn’t, lets get a discussion going about this seeing as we are in for a nice warm summer.
 
OK, I promised a “new” idea, and although I am sure someone somewhere has tried this, I have never read about it.
One of the tasks we are constantly doing is water changes. I like to do 15 gallons a week, siphon out the old, and after mixing and heating my make up water, adding the new. I was thinking, why bother heating the makeup water, what if we could devise a system via the use of controllers, pumps, float switches or whatever that monitored tank temp and when it rose above a certain parameter, old tank water would drain and be replaced by new cool saltwater. The saltwater in my mix tank is about 70 degrees and if added SLOWLY to replace 82 degree tank water it should in theory bring tank temp down. Why not use something we already do to kill 2 birds with one stone. This would have the added benefit of automating the waterchange process, your system would constantly be draining off small quantities of old water and introducing new cooler water. There are so many variables and contingencies to figure out, but I think it might work.
Comments?
 
I've done the ice bag thing - it works in a pinch. We use room A/C in the house cuz hubby is something of a gorilla anyway, but I did ice dips the past couple of days (our fridge makes ice so never ending supply) since we hadn't put it in yet. I just throw a bunch in a ziplock, clip it to the top edge of the tank with a big binder clip and let them melt. The tank was a nice 77 degrees while the house was 82... Damn glad we got the AC in today...

We checked into central air - were told we would have to replace the furnace... $9K = no way...\

We are going to do a DIY LED system when we upgrade - I have the LEDs already - just need to get the fixture we'll gut for the housing, the power supplies and controller. Going with 72 3W LEDs and dimmable drivers. It's a 110 tall so 1W wouldn't do it. Hubby is really handy - he's building the stand, etc also. I <3 that man ~
 
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The saltwater in my mix tank is about 70 degrees and if added SLOWLY to replace 82 degree tank water it should in theory bring tank temp down. Why not use something we already do to kill 2 birds with one stone. This would have the added benefit of automating the waterchange process, your system would constantly be draining off small quantities of old water and introducing new cooler water. There are so many variables and contingencies to figure out, but I think it might work.
Comments?

Never tried this and I have no clue as to the actual science of it, but just using thinking things and it seems that eventually, and rather quickly would be my guess, "small quantities" would just rise to the temp of the surrounding water. And if it did drop the water temp a few degrees it seems it would only be for a small amount of time. I think you would need a pretty constant supply of "cooler" water flowing into the tank. Maybe being pumped out of the tank and cooled elsewhere and then re pumped back into the tank in a closed loop? Not sure, just some late night thoughts
 
I have a dozen water bottles I keep in the freezer. I can use 4 at a time to drop the temp in my tank by a couple of degrees.

It's not the most elegant solution, but it only cost pennies.

I would like a window a/c unit for my home office (where the tank is), but my wife has nixed the idea so far. Maybe this will be the year my funding request gets approved! :)
 
A very strong fan blowing directly across the water surface in your tank can pull down the temperature substantially. Even with 600watts of light, I am able to keep my tank at 80 until it gets above 90 degrees inside my apartment. This is similar to a what a small chiller would be able to handle. Once it gets above 90 in the room I let the chiller run, which of course makes it even hotter, but at that point the room is so far beyond comfortable that it doesn't matter if it gets a little warmer. If it is one of the 100 degree days, I just leave my lights off for the day. No harm in a day or two without light(as long as your PH isn't crashing).

If I didn't live in an apartment, I would absolutely do AC for the fish tank room + a chiller. So much more comfortable for everyone involved, and so much easier to manage.
 
Never tried this and I have no clue as to the actual science of it, but just using thinking things and it seems that eventually, and rather quickly would be my guess, "small quantities" would just rise to the temp of the surrounding water. And if it did drop the water temp a few degrees it seems it would only be for a small amount of time. I think you would need a pretty constant supply of "cooler" water flowing into the tank. Maybe being pumped out of the tank and cooled elsewhere and then re pumped back into the tank in a closed loop? Not sure, just some late night thoughts

I am inclined to agree with Saltwater Stu that this would have little impact; what impact it has would be temporary and it would get expensive during a heat wave. I never heat my water change water, I do about a 15% water change weekly (55 gallon WC for 400g system). This is all dumped quickly into the sump and will drop the temp in the sump from 81 degrees to 74-76 degrees. However; once I turn on the return pump and everything mixes I may see a 1 or 2 degree difference in the entire tank. You might get a little more if you were to keep the WC water cooler - store in the garage and mix by hand? Mine is stored in the closet in the fish room and mixed for 3-4 days with a pump before use.

I use a window AC unit to keep my tanks cool in the summer and an open window in the winter except on the really cold days (sustained below freezing). Window AC units are not really that expensive (much cheaper than a chiller for the tank) and they also provide the family/household occupants relief from the heat! As long as you have good airflow around the tank you really do not need to keep the room real cold, our AC is typically set at 76-78 depending on the weather forecast. If it was forcast to get to 100 I would turn it a little lower so it would start up sooner. When I had MH I also set the controller up to shut down one set of lights if the temp went over 82 and all lights if it went over 83, only had that happen a couple of times (this was before the AC). Switching to LED has made a big difference in temp control.

Also I would disagree with making the wife happy with a 65 degree room, I fought AC for years as I sit in it all day at work and freeze! My husband was only able to get my approval for one when the heat spiked in my tank one hot summer day (lucky him) now we battle over the temp setting-he would keep it below 70, I prefer the 76-78 . . . .
 
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Heres one for you coil up about 100' of 1/4" hose in the bottom of your refrigertor/ veggie drawer. Drill the size hole needed in the back of refer at motor area install hose and seal opening with silicone inside and out. Run hose to sump and install small powerhead with valve on a open loop so that you have a constant drip of nice co..............ol water. Will not hurt refrigertor if done right so use a bit same size as tube and seal, i did this for three years with my 750 using my shop refer. It has to be a drip so water comming in has time to cool once set up adjust as needed.
 
You could do the same thing using an ice chest install coil pack with ice and drip. An ice chest indoors could last a couple of days and would be even easier if you have an ice maker:)
 
Heres one for you coil up about 100' of 1/4" hose in the bottom of your refrigertor/ veggie drawer. Drill the size hole needed in the back of refer at motor area install hose and seal opening with silicone inside and out. Run hose to sump and install small powerhead with valve on a open loop so that you have a constant drip of nice co..............ol water. Will not hurt refrigertor if done right so use a bit same size as tube and seal, i did this for three years with my 750 using my shop refer. It has to be a drip so water comming in has time to cool once set up adjust as needed.

Before I start, let me say that if Spinner says that his set up with the shop refer was effective, I am not saying he is wrong, I sincerely do not intend to start a ruckus, but rather would like to offer a few words to perhaps save someone else from wasting a lot of time and money.
The dorm fridge chiller debate comes up every summer on reef boards everywhere. The idea is attractive, a 50 dollar craigslist dorm fridge, some plastic tubing, a pump, maybe a controller, and voila cheap cooling for your reef. For everyone who swears they have built one that is effective, there are a dozen posts explaining why this simply isn’t practical. Typically when people report building a chiller that works, there is some unmentioned variable that renders the project moot, such as they also have air conditioning in the house, or they have a 1000 dollar a month electric bill, or the chiller ran awesome for 3 days then died. . Room size, room temperature, water temperature and energy cost to cool all need to be addressed. I think one year on one of the boards I suggested a contest that people build there own DIY chiller with a set budget and bring them to the Bob Moore or some other club event and show off their handiwork. It is a fun project simply from a geek point of view, but from what I’ve read, it is not practical. With my limited scientific knowledge I couldn’t possibly explain this as well as others have, so rather than reinvent the wheel, please refer to the following article on this. It is an awesome article.

BeanAnimal's Bar and Grill - Dorm Fridge Chillers Fact and Fiction

Again, Spinner, I am not challenging your claim to an effective result, if you say it worked, ok, I am just trying to save some others some aggravation.
 
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rap that coil around ur kegorator now thats an idea ot take apart a water despenser cooler and make ur own
 
Hello Ichthys,
No worries with anyone ever questioning anything i write that is what make's America great and one way new things are invented:) I must say though i never said it was a home made chiller only an option to help bring down aquarium temp. a few degrees. I had a chiller on my 750 with 300+ corals no way would i rely on my diy refrigerator drip to keep my tank in check.
There is so many factors with everyones set up that it would be impossible to say it would work for everyone. In my case the shop refer was cut into my breeze way wall putting the back of the refer only three feet away from my refugium in my fish room. Yes heat from refer was vented to the outside:)

An easy and maybe fun test would be the ice chest one although i have never done it that way, i would bet the water comming out will be cooler than the water going in? Also i wrote to use a powerhead i ment a dosing pump sorry about that:)

Another option is to freeze water in a plastic bottle/milk jug and set in sump alittle easier than ice in a baggie:)

Here's to cool reefs in the summer!
 
When I had my 75gal, I had 3 fans sucking hot air out of the canopy and 2 fans blowing in cool air across the surface of the tank. I also removed the back I had on the stand to allow the sump to breathe a bit and put a big clip on fan over the sump. These were all on timers that came on when the halides came on (dual 250w halides) and turned off an hour after the lights went off. This kept the tank cool and at the right temp, but I lost a lot of water through evaporation as well as I felt a bit un-easy leaving everything up to fans so I bought a chiller as well. When I get to my computer I'll post a few pics. :)


Sent from my iPhone using Tapatalk
 
I have done the floating frozen water bottle thing for years with my fresh tank. This is my first summer with a salt tank so I'm glad to hear it is good for it as well. Bonus is I can do it in the sump so it still looks alright :)
 
Well I finished reworking my fans this evening. I have 2 Koolance 140mm 12v fans blowing into the hood, directly towards each MH light, and 2 Koolance 120mm 12v fans blowing out of the side of the hood. I used something called speaker cloth from Joannes fabrics to cover the holes in the sides, and trimmed them in oak, they look nice. All 4 fans are plugged into 2 separates 12v rails of a Dell 300w power supply which is plugged into my Reefkeeper controller and set to come on when tank water goes above 79. Will graph temps over next 2 weeks and then maybe play and adjust.
 
I use to run my lights at night. This will work if your temps are cooler outside at night. You have your tank close to open window
or run a air exchange system at night.
 
Hey,

I installed a two speed window cooler today that sits at the far end of my build. 16' long from tank to end of reactors then turns right>:) It's a BRISA two speed on low i can feel the breeze 20' away from unit. I have A/C but this will work well up to 85 deg. then A/C for about two months straght 100+
 
Bunch of great ideas ~ will definitely do the water bottle thing if I need to. Sounds MUCH easier than ice in baggies.
:love:
 

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