Insulating my system

ReefEnabler

Premium Member
Been awhile since I've posted here...

I've been noticing that on cold nights, my heaters run almost nonstop, and I have the energy bill to prove it.

My system is a 220g (glass) display located inside the house, and a remote fishroom in the unheated, but somewhat insulated garage. The garage houses the 70g sump, 50g fuge and 50g waterchange tank, all 3/8" acrylic. My garage can get pretty cold when it gets near freezing temps outdoors.


I run two 500w and 1 250w titanium heaters controlled via Ranco. Also run a 1/2hp chiller that is outdoors which all return water goes through, even though the chiller doesn't really get used during winter. I recently insulated the outdoor plumbing. I may choose to put a 'winterization' valve to isolate the chiller during winter, but I'm not sure what kind of savings that would result in now that the pipes are insulated?

Currently, none of the tanks in the garage have lids. That's my next plan of action, putting lids on the Fuge and Waterchange tank. Probably a big savings there?

I'd also like to make a lid for the sump, but due to the skimmer and various wires/pipes it will be very tricky, but I can possibly do it using 3-4 different sheets of acrylic with swiss-cheese holes drilled (sounds fun right?). I think I can see a pretty big energy savings by doing that.... but would it be worth it? Or is there another way to somehow contain the water vapor in the sump? Maybe some vinyl/zipper barrier?



I am curious if there is much to be gained by insulating the garage tanks as well??? The tanks sit on a sheet of polystyrene, but would it help much to put polystyrene on the sides/top also?
Does anybody know the R-value of 3/8" cell cast acrylic??? Would this be in diminishing returns territory? Any better suggestions for holding in the heat longer?
 
I would definitely bypass the chiller, and start with some blueboard foam for tank lids..( just that might save you about 50%)....easy to cut ..cheap...and waterproof...with an r-value to boot...you could even make a box of it to insulate the sides....good luck
 
You have a lot working against you. You certainly should bypass the outside loop.

Evaporation: You get over 8,000 BTU's of cooling per gallon of water evaporated. You can easily calculate how much heat you are losing through evaporation by simply noting how much water you evaporate per day. After placing covers on the garage sumps, you can note the difference and see how much the covers are doing.

Convection and Conduction: The garage sumps (and tank in the house for that matter) also lose heat to the surrounding environment due to conduction and convection. While we can calculate this loss, the process is somewhat involved. In a nutshell, the larger the difference between the ambient room temperature and the water temperature, the faster the loss. Adding insulation under the tank, and too the tank walls will certainly help. Foam insulation board is likely going to be the easiest to work with. You can use adhesive backed velcro to make simple straps to create an easy to setup or remove insulation system.
 
A cover will do wonders for your heat loss. I like the idea blueboard, it's cheap and very effective but it doesn't do well when light transmittance is desired.

I am guessing that 3/8" acrylic will give you an R value of less than one. It is it's ability to stop evaporation and radiation of the water AND still permit light thru that makes the magic.
 
I have a 180 gallon freshwater that I was having a hard time heating. Two 250 watt heaters were running non stop. I went to the store and picked up two simple pieces of glass. Cut them to fit the aquarium. I think I spent a total of about 12 dollars. In my case just this simple top and I have cut down to one heater and it is not running non stop.

My tank is in a finished basement that stays at about 70 degrees year round so you might need some insulation but I would try the cheap glass trick first and see if it helps.
 
i had a 300 gallon with 3-500 watt titaniums heating it to 82(planted freshwater discus tank) and in the winter i would have to put foam on the panels of glass to keep it warm, my tank as in the basement at a steady 60 degrees
 
thanks for the tips.

sgolden, I will certainly plan on bypassing the chiller sometime soon, but I think I already missed my biggest window of opportunity for this winter...

bean, love the velco idea for attaching insulation to the sides. I'll try and test the evaporation soon. I'd probably have to leave the ATO off for a whole day to be able to get a meaningful measurement on the side of the sump.

I just got done making a lid for the refugium using some 3/8" acrylic scrap. I put some EPDM around the edges and even cut a hole for the plumbing to enter nicely end sealed that up too.

After only 30 mins or so I already see condensation and vapor inside the sealed space. So looks like it was probably a huge source of evaporation given the PVC spray bar.

I'll use a thick piece of foam for the waterchange tank, will be much easier to cut holes for plumbing.

I did a really quick hack for the sump: cut a piece of plastic drop cloth, cut some holes for probes, reactors and skimmer intake, and tucked it around the sides of the sump. I'll need to get a piece of foam for that too.
 
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I put a portable dehumidifier on for ~2 hours last night and it was able to pull the humidity in the garage down to 43%!! That's a really huge improvement so far, before I could leave the dehumidifier on all day and it only got down to the 50's since water would probably just evaporate as fast as it was removed.

I haven't had it on at all today so I'm curious to see how much the humidity rises back up on its own today.

This should make my tools alot less rusty :)
 
Does anybody know the R-value of 3/8" cell cast acrylic??? Would this be in diminishing returns territory? Any better suggestions for holding in the heat longer?

Anyone have a good reference on the web for R values of different materials? I'm trying to figure out how much "value" I'd get insulating my build, which involves plywood, 2x4 lumber, drywall, glass, and epoxy.
 
DWZM (if you dont mind),
I've been following your build thread and greenreefing threads. The plywood display looks excellent, can't wait to see it filled up, I'm sure the white will be a nice change.
Should get some nice energy efficiency with that + wooden sump, but I'm curious how far you take the 'green' concept since I am using you for inspiration to tweak my setup :)
 
DWZM (if you dont mind),
I've been following your build thread and greenreefing threads. The plywood display looks excellent, can't wait to see it filled up, I'm sure the white will be a nice change.
Should get some nice energy efficiency with that + wooden sump, but I'm curious how far you take the 'green' concept since I am using you for inspiration to tweak my setup :)

Thanks. Of course it's early to say this, but I'm pretty sure my tank is going to run cool if I don't take some sort of measure. It's going to have ~400g of system volume, and only ~300 - 400w of LED lighting. I keep my house cool year-round (in the mid 60's). The tank will be built in a wall, hence I'm wondering if it's worthwhile to make room in the wall for insulation. I'll probably do it anyways but I'd like to have an idea about what the effect will be. Besides insulating, I'm probably going to do some sort of "heat recovery" in terms of turning fans on/off or moving baffles in duct work to point the warm air coming off the lights towards the tank or out into the room. At most, I'm still thinking about tying in my home's furnace, though that's another can of worms.

Plus I have some of the same questions you're asking - do I cover the sump? Do I cover the DT? At what point will the loss in gas exchange outweigh the savings in heating cost? And so on. So I'll be watching your results.

As far as how far I'll take the "green" concept, I suppose that depends on your meaning of the word. I care about trees and all, but one of my main motivations for "green" efforts is simply cost. :) It's cheaper to not have heaters running 24x7!
 
Just had another thought... If acrylic insulates much better than glass, people with glass tanks could make an acrylic sheath to cover the display tank, possibly bond the sides and front so the acrylic can stand on its own, and use a bit of weatherstriping at the top since heat rises... Worth doing for people with glass tanks and cold houses?

Of with a wooden tank you could make 1 removeable acrylic insert piece to cover the glass...

might be a pain to move that big shield for a large tank, but if you can take it off and safely store when not needed, it might not be so bad.
 
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Im in a similar situation. I have a 300g with a 200g sump and two 40g frag tanks which are located in my basement(which got into the low 50's earlier this month). I had 2000w of heaters in there and that was barely keeping the tank at 71.

Ill be putting up some of the blue foam next weekend, and making acrylic covers for everything.

Im hoping to avoid having to wall off the fishroom just so I can heat it.
 
Had another thought last night:

Wouldn't the skimmer's exhaust air be some of the most humid coming out of the system??? I already have a bathroom-fan style exhaust in the fishroom, what if I just drilled a hole into this 4" metal duct and ran some rubber tube from the holes in my skimmer lid into there??? Would the fan suck the wet air out of the skimmer exhaust, or would it create pressure that might make it harder for the skimmer to vent???

Might rust the inside of that exhaust duct but the duct serves no other purpose (just goes outside) and will have to be removed when I sell the house anyways.

I got some sheets of 3/4" (thickest they had in) blue foam with an R-value of 4, now just need to cut it up and attach to the sump/refugium/waterchange tank. Have family visiting right now though so it's made it difficult to get stuff done.
 
quick diagram incase it's not exactly clear:

skimwet.jpg


Would this prevent the skimmer from exhausting air when the fan is on, or would it just suck the air out from the skimmer no problem.... would it help if I found a way to have the tube continue inside the duct so the air exits in the direction of the vent airflow (instead of just sticking in at 90 degrees like a venturi)???

Ryan
 
The fan discharge duct is under a positive pressure. You won't get any extraction from your skimmer with that installation.
 
The fan discharge duct is under a positive pressure. You won't get any extraction from your skimmer with that installation.

It is not as cut and dry (no pun) as that.

1) The pressure in the fan duct is very minimal, even for a modest sized fan with a reasonable lenght of vent tube and exhaust damper.

2) The skimmer's air output is under positive pressure. Depending on the skimmer type this could be significantly hiigher than the pressure in the duct.

3) For any reasonable flow in the duct, the skimmer air output will be subjected to negative pressure (suction) due to the Bernoulli principle (venturi effect). That is, the skimmer's air output is a pitot tube in the duct and the flow of air past it will cause a negative pressure over its opening, thus producing a suction that will help draw air from the skimmer.

That said... I don't know that it is worth the trouble :)
 
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