Rate of evaporation?

[whosinpower]

I have a 90 gallon reef tank with a sump. We have had it set up for a couple of months.

Our rate of evaporation is almost a gallon a day! What is yours? I'm having trouble with humidity in the house. Windows are all sweating - it is winter up here and outside temperatures are -15 to -20 degrees celcius.

If I put a glass cover over the sump - would that help? Is that a bad idea?

Not wanting to buy a dehumidifier - but is there any alternatives?

thanks!

[pablodub01]

That pretty much depends on the lights you have and how close they're to the water surface... i have a 50 gallon tank with 1x150w MH and evaporation is roughly 1 litre a day...

having fans also help to reduce the temp in the water surface and reduce evaporation...

[spellbound]

We have different rates of evaporation. During rainy season we lose about 2-3 gallons a day from our 125 gallon tank. Now during dry season we are losing 5-6 gallons a day. Fortunately my tank is in a 3,000 sq ft store. Humidity has not been a problem.
Hopefully someone with experience will help with the covering the sump. Personally I don't see a problem covering the sump, but I could be wrong. If you don't want a dehumidifier, I'd try to cover the sump, unless someone knows this could be bad for your system. You may still find you need a dehumidifier after covering the sump.

[Sk8r]

I evap about a gallon a day from my 54g.
Tops open assure good gas exchange and temperature control, both for the health of the tank. It depends on how efficient your tank is at doing these jobs elsewhere, as in the downflow. I could not stabilize my temperature until I tossed the last segment of lid in my sump.

[EdKruzel]

I'll assume the tank is in a small room if you're experiencing condensation on your windows; you could open the windows slightly to allow some of the moisture to escape or vent the room to distribute that moisture into the rest of the home. You of course don't want that much moisture in one area, but letting it vent through a larger area will help to make cooler temperatures feel more comfortable and help reduce your heating bill.

[MTB]

I had to install a fan near my tank to vent to the outside. It was a little cheaper than buying a dehumidifier and made a huge difference. It's basically a bathroom fan kit on a hydrostat(I think that's what they called it). Opening a window may help. Or you could try a window fan if the open window isn't enough. I would only do the window fan if the room can be closed off to the rest of the house. Don't want to suck too much heated air out.

[whosinpower]

Opening a window is not an option - our outside temperatures in the winter range from -10 to -30 degrees C.

Aquarium is in the lower level of a bilevel house - house is a fairly open concept and all the windows in the house are sweating including the bedrooms. Tank is not close to furnaceroom and furnace is drawing air from outside - not inside.

House never did this before the tank - however, we did have a new furnace installed - are going to have the furnace guy come back and trouble shoot as well. I think it may be a combination of two issues - the tank and the new furnace.

I was hoping that covering the sump would help - but do not want to impede gas exchange as another poster had indicated.

[irishsea]

750 lt tank and about 5gals aweek.

[omacphe]

whosinpower

Do you have a humidifier on the new furnace? If so can you turn it off for testing?

What is the temp and RH in your house?

Hope this isn't too obvious but, it would be a good idea to try to reduce the amount of water getting into your air from other sources (bathrooms/kitchens/laundry rooms). For example, I have my bathroom fan wired directly into the light switch so unless you shower in the dark the fan is running. If you have an exhaust fan in the kitchen use it when washing dishes. Do a quick smoke test to make sure these fans are all drawing well (talc also works nicely for this).

If you're in a new house it may be so tight you're having trouble getting make up air with the fans running. In this case you need to talk to your furnace installer.

Cheers,
O

[dantonac]

Your new furnace almost certainly has a humidifier on it. The winter air is very low in humidity so lots of static electricity and nose bleeds occur if something isn't done to raise indoor humidity.

With my furnace humidifier I can make the windows sweat if I turn it all the way up.

Check that first. It's unlikely 1 gal of water per day from the tank is enough to make the windows sweat. Before I got the whole house humidifier I was using smaller humidifiers and went through about 6 gallons per day in them with no window sweating.