Cold basement!

[Willistein]

Anybody else struggling with keeping tank temps up? My basement was 53 degF last night. I didn't like doing it, but I had to throw another heater in my sump as the tank was struggling to stay above 72. Corals look happy, but I got nevervous when I saw 71.4. This morning it was 77. I think having added a second 40BR with all of that surface area effectively doubled my heat loss. I'm sure that the majority of the heat loss is the evap heat loss - heat of vaporization of water is HUGE, Rochester!

What are you guys doing to combat this?

My wife suggested the permanent solution of moving south...

 

[mr.maroonsalty]

Wouldn't hurt throwing a survival type blanket over the tanks down there to combat radiational cooling. It would save a few btu's.

 

[MarksReef]

May this be the only time I give the advise of listening to your wife :wildone:

 

[duckmeat]

last winter i went ice fishing one day, and the house door didnt latch when i left...i was gone about 12 hours, furnace was running nonstop, and my tank was 63*... everything survived...

 

[Vinny Kreyling]

Cover the sump as best you can to prevent evaporation.

 

[Willistein]

So, I've been interested to know exactly how the heat is being lost because there is quite a lot going on. Heat loss from an open tank is made up of heat loss from the water surface and heat loss through the glass sides and bottom.

For heat loss from the water surface, I found a calculator developed by a couple profs at UDayton and plugged numbers in. Now, this doesn't take into account the chilling effect of the skimmer pulling cold air in and exchanging the heat quite effectively with the water around it.

assumptions
40BR tank = 36" x 18" surface area.
No fans, so still air
50% relative humidity
air temp = 54 degF
water temp = 78 degF

Heat Loss through surface of water only:
water evaporated per hour (mass loss rate) = 0.1 kg/hr
convection heat loss = 23 Watts
radiation heat loss = 30 Watts
evaporation loss = 75 Watts
Total = 128 Watts

Double this for two tanks and I have 256 Watts for the two 40BR tanks

For the 120 DT in a warmer room (68degF) the numbers are:
Heat Loss through surface of water only:
convection heat loss = 13 Watts
radiation heat loss = 23 Watts
evaporation loss = 81 Watts
Total = 118 Watts

The grand total of all three tanks is: 374 watts

I haven't calculated heat loss through the glass, but I'm guessing it is pretty minor.

The point is, I need to cover my tank or put floating balls in it, because evaporation is the main heat loss component.

 

[Willistein]

The program is called HeatSim and is available here:
http://academic.udayton.edu/kissock/http/RESEARCH/EnergySoftware.htm

 

[saltyscotsman]

I have my 100gal sump covered with 1"foam insulation and a 1000watt heater for 240gal system never have a problem [so far]!!!!!!!!!!!

 

[mr.maroonsalty]

I would like to know, My bet is radiational cooling is more than you think.

 

[timkatz71]

What type of heat do you have in your home?

 

[MatAndPatti]

I came across this calculator a while ago. I didn't actually use it so can't vouch for it, but it looks *insanely* detailed.

http://www.hamzasreef.com/Contents/Calculators/HeaterChillerInstructions.php

 

[reepher315]

Also struggling to keep temps up and evap down. That styrofoam top sounds like a great idea.

 

[pascal32]

I used to have a basement sump - a lot of heat loss no question about it.

Keeping the tank off the ground helps. I dealt with it, though covering the tank and wrapping it wouldn't hurt.

 

[intyme]

Insulate everything, plumbing, sump.

 

[pascal32]

good call on the piping, never thought of that. pipe wrap is cheap and easy to procure.

 

[Gary Majchrzak]

It's extremely cold and dry this winter.
This will affect RO production as well as evap rates.

Basement aquarium plumbing should never sit directly on concrete slab.

Cover the sump in cold dry weather to minimize evap and aquarium heat loss.

Turn the the house temp up to 68 once in a while

 

[Willistein]

I have gas heat so it's cheap, the problem is, half of my house was built in 1880 and has stone walls.
Mr maroon, I was curious too about which was the predominant heat loss mode. On the surface of the water, if it is uncovered, evaporation dominates. I'm guessing on the side walls of the tank, radiation dominates. If the tank sits on a cold slab, conduction would probably dominate.
My sump is up on a table next to the frag tank. I only had two 250watt heaters in there, so no wonder it couldn't keep up.

 

[timkatz71]

Gas forced air or baseboard?

 

[94lsxs10]

My sump is a 40 breeder. According to the Apex my 400 wats of heaters are on for 2 hours then off for 2. Tank temp is between 77-78. House is 68 and basement is usually 60-62.

I'm burning top off water though about 5 gallons every 3 days, the house is so dry right now.

 

[Willistein]

Gas forced air or baseboard?

forced air