Fans or Chiller?

[falconut]

I'm trying to decide between a 10 year old Aquanetics 1/4 HP chiller or just adding additional fans.

I have a 90 gal. reef tank w/(2) 250W MH bulbs running 7.5 hours. The setup was built into the wall. During the spring, summer and fall on hot days it can build up heat. It's been running for over 4 years with fans. But it can get up to 83 - 84 degrees somedays. I have to open up the lower cabinet doors and open the closet door.

Recently I was trying to decide if it would be worth it to buy a 10 year old chiller. It would have to sit on my living room floor, but would fit under one of the chairs. I was told that it only comes on when it is cooling, not continuously. It would have to be plumbed through the wall though. I've never had a chiller, so I don't much about them.

I do have central air, but I hear it from the wife on days where the windows could be open if it were not for the tank.

Which method sounds like the best option? Opinion are very welcome as I'm not sure what I want to do yet.

Thanks.

 

[Savas]

I would take the incremental approach - try the fans first and see if they cool enough to your liking. Cooling efficiency and technology has changed over the last 10 years, so I would try to buy a new unit, just to save on operating costs. Just my thoughts..

 

[scbauer]

I have to agree that a chiller that is 10 years old is most likely very inefficient by todays standards. I would also bet that it is fairly loud, but just a guess.

I say add a fan or two... this approach help me a LOT with my last tank. I had 1 fan that was lower than the top of the tank, pointed up at my 250W MH pendant, essentially blowing the hot air away from the surface of the tank. A second fan was right above my sump and blew directly on the surface of the sump water. This was what really helped the temp but also dramatically increased evaporation, so you have to be able to handle that.

Just as a reference, my 29-gallon tank evaporated about 1/2 to 1 gallon per day with the fans.

-Scott

 

[scbauer]

If the fans don't meet your cooling needs, then try a chiller, but look into a new, quiet, efficient chiller.

-Scott

 

[Savas]

The newer units are also smaller and quieter.

 

[greenbean36191]

I would say neither if your high temp is 83-84. That's pretty much the optimal temp for most corals and is well below the average high for coral reefs and even further from the upper limits of safe temps. If my tank only reached a high of 83 I'd be in the market for a heater rather than a chiller.

 

[scbauer]

I think the argument of "correct tank temp" has been covered many times and I think the better question is of temperature stability. If falconut likes to run his/her tank at 78 then it would be bad for his temp to go up to 84, then back down to 78.

A good chiller/heater combo, in my mind, is the key to temperature stability.

-Scott

 

[Longchamp]

Fans can do it. Use them until your evap/humidity gets out of control.

 

[Steve 926]

you mention that the display is an in wall set up, with a closet.
can you install an exhaust fan to vent some heat out side, or to an attic space. this plus a good fan will dramatically help.


Steve

:smokin:

 

[mikesommers]

I live in Georgia. My tank would reach a temp of 86 in the spring. Corals were closing, fish were hiding. Remember that the higher the temp the less dissolved oxygen. So I decided to add a Pacific Coast CL450 1/6hp chiller and a 200 watt heater that plugs into the side of it. Works great with only one problem! Guess what the chiller puts off on those days when the tank would be 86. HEAT!!! That's ok though its not that bad. You have to vent the chiller, VIA fan A/C vent or so on. So my final fix is a basement sump one day (when my wife says ok)!!! Its in the works. For now it sits under the cabinet, I removed the door on that side. Evap went from 2.5 gallons a day to 1 gallon every other day. Corals are loving it and fish are happy!!!

Good luck!

P.S. Pacific Coast Chillers are great low cost and welllllll worth every penny!!

 

[atvdave]

<a href=showthread.php?s=&postid=12381049#post12381049 target=_blank>Originally posted</a> by greenbean36191
I would say neither if your high temp is 83-84. That's pretty much the optimal temp for most corals and is well below the average high for coral reefs and even further from the upper limits of safe temps. If my tank only reached a high of 83 I'd be in the market for a heater rather than a chiller.

I agree.. Keep your temps in around 81 or so in the summer so there's not as much temp swing.

But a temp at 84 is nothing to panic about. Fans do a good job.

 

[falconut]

I'm seeing that I should pass on the old chiller. But here are some answers to some of the above.

My tank is usually between 79 - 81, being that is usually is 80. This is where it seams to stay most and thus where I try to keep it.

I have thought about venting the closet/wall (it is all one space in the wall, I built it out from the existing wall). It is on the 1st floor, under the Master bedroom, so I don't have access to the attic. It is also in the middle of the house, so I don't have access to the outside. So the only venting I'll be doing is out of the closet into the living room.

I currently run an old Humidifier fan (10" dia. blowing on the sump) and about 3 - 4 small computer fans scattered in the upper part of the closet (they just help direct the air out the vent I put above the door. In the summer, I usually add a 6" fan and direct it at the MH bulbs, but this fans is usually only good for 1 year and won't start the next year.

If I go with additional fans, does anybody have a good place for getting quiet high CFM fans? I may start replacing the CPU fans with better ones, I just have to find some.

Thanks for the Chiller opinions, look forard to the fan advice.

 

[BigJay]

What are your opinions on the evaporative chillers?

I'm talking about the "swamp cooler" types that use little power since they aren't condenser-based.

Are they any better, worse, or the same as having PC fans over your tank?

 

[greenbean36191]

Ok, 3 common temp myths to bust here.

1. Keeping the temp lower will give you more margin of error before you hit dangerous temp. No, it lowers the stress threshold of the animals as well and you end up with roughly the same margin of error. An animal that would normally be fine to about 88-90 degrees starts to show stress at 86, which is within the yearly average range for coral reef worldwide. There are very few corals except those from unusually cool areas like Hawai'i (where corals aren't collected) that would be expected to show stress at such low temps.

2. Keeping temps lower improves your oxygenation/ makes it easier to breathe. Yes, but over the range of temps in the hobby the difference is negligible (In the neighborhood of 6% difference). Even at 90 degrees the oxygen saturation point for seawater is more than double the safe minimum. Metabolism does increase with temp, but again over the range of temps you would see in a reef tank the change is pretty small unless you've gone past the stress threshold for your animals. In that case it jumps up pretty quickly. It's quite easy to maintain O2 saturation comparable to nature in a normally stocked tank regardless of the temp. If the power goes out hypoxia can occur so quickly that your temp at the time doesn't really make much difference.

3. Fluctuations are stressful to reef animals. Well that depends. A "typical" coral reef will see 3-8 degrees of variation per day, with some varying by as much as 15 degrees per day. And it doesn't take all day to see that change. It occurs on the order of seconds to minutes. It's well documented that single points on the reef can see half of the yearly variation within 1 minute! Needless to say, reefs are not thermally stable environments and the animals there are well adapted to deal with the changes. However, like their their upper thermal limits, their tolerance for fluctuation can be modified through acclimatization. All you have to do is change the temperature interval they normally see. You can take an animal that normally tolerates 10 degree/day changes, keep it in conditions where it only sees .5 degree/day fluctuations for a few weeks and then severely stress or even kill it by subjecting it to 3-4 degree changes. It has nothing to do with the innate ability of the animals to tolerate fluctuations and everything to do with the conditions they were acclimatized to. So how do you keep fluctuations from stressing out your animals? You let the temperature fluctuate regularly. If you don't, when something goes wrong and your super stable temp varies a bit then you've created a self-fulfilling prophecy with regard to fluctuation induced stress.

There's absolutely nothing worrisome about a tank that's normally 79-81 and sometimes gets up to 84.

 

[mikesommers]

<a href=showthread.php?s=&postid=12384452#post12384452 target=_blank>Originally posted</a> by falconut
I'm seeing that I should pass on the old chiller. But here are some answers to some of the above.

My tank is usually between 79 - 81, being that is usually is 80. This is where it seams to stay most and thus where I try to keep it.

I have thought about venting the closet/wall (it is all one space in the wall, I built it out from the existing wall). It is on the 1st floor, under the Master bedroom, so I don't have access to the attic. It is also in the middle of the house, so I don't have access to the outside. So the only venting I'll be doing is out of the closet into the living room.

I currently run an old Humidifier fan (10" dia. blowing on the sump) and about 3 - 4 small computer fans scattered in the upper part of the closet (they just help direct the air out the vent I put above the door. In the summer, I usually add a 6" fan and direct it at the MH bulbs, but this fans is usually only good for 1 year and won't start the next year.

If I go with additional fans, does anybody have a good place for getting quiet high CFM fans? I may start replacing the CPU fans with better ones, I just have to find some.

Thanks for the Chiller opinions, look forward to the fan advice.

80 degrees is were I keep my tank. That's fine as long as it doesn't climb up during the day. I still say you would love a chiller. I would not use any other method ever now that I have used a chiller. I love mine.

 

[nhlives]

Three small inline fans over the fuge keeps my temp within .5 of 78.0. I used a different system of fans last summer with good results. Fans are cheap to buy, cheap to operate and quiet.

 

[smcdonn]

Evaporative cooling is very powerful, just don't think that your saving all that energy by not running a chiller. Your A/C has to pull that moisture out of the air and your central A/C isn't cheap.