Large Tank IN a Basement-Ventilation Suggestoin Please oh brethern of the mamoth tank
- Thread starter skippyreef
- Start date
I'm planning for about a 180g tank in my basement. How feasible would it be to basically seal the canopy over the tank and vent it with an exhaust fan out through an exterior wall? I realize this wouldn't be a true seal because of holes for electric cords and whatever cooling fans were being used to bring air into the canopy.
Since we live in Portland, OR we don't really have extreme temperatures. We leave the basement door open to the garage most of the time so the pooch can do what it wants. This makes me think I could probably vent air into the basement to combat any negative pressure issues without disrupting our comfort level or using a lot of extra heating/cooling energy.
This is new construction by the way, gas furnace and central air but we don't run either very hard. Sump will be in the garage.
Since we live in Portland, OR we don't really have extreme temperatures. We leave the basement door open to the garage most of the time so the pooch can do what it wants. This makes me think I could probably vent air into the basement to combat any negative pressure issues without disrupting our comfort level or using a lot of extra heating/cooling energy.
This is new construction by the way, gas furnace and central air but we don't run either very hard. Sump will be in the garage.
Whaledriver
New member
Brad W
Why not have a fan in and a fan out? They should balance each other out and limit the suction of air out of the house.
Why not have a fan in and a fan out? They should balance each other out and limit the suction of air out of the house.
Capncapo, is there a particular fan you would recommend that could handle the high temps and humidity? There will be about 20' of duct.
Whaledriver, your idea makes sense. I'd like to avoid running another duct if possible (and trying to locate it far enough from the output of the other fan) plus the additional large fan (more electricity, etc.). I was just hoping to use a few of those 4" icecap fans for air input and cooling in the canopy and then maybe just a passive vent on the exterior basement wall somewhere for the negative pressure thing. The ducting will actually be going through the basement wall and then through the garage's exterior wall. Your way definitely sounds more bulletproof though.
Whaledriver, your idea makes sense. I'd like to avoid running another duct if possible (and trying to locate it far enough from the output of the other fan) plus the additional large fan (more electricity, etc.). I was just hoping to use a few of those 4" icecap fans for air input and cooling in the canopy and then maybe just a passive vent on the exterior basement wall somewhere for the negative pressure thing. The ducting will actually be going through the basement wall and then through the garage's exterior wall. Your way definitely sounds more bulletproof though.
Whaledriver
New member
Intead of the Icecap fans you might try some inexpensive computer case fans. Just have them go on and off with the lights and you should be fine.
That's weird capncapo, we must have posted at almost the same time.
Yeah, I had a feeling you'd have something to say about evaporation even when the lights are off.
By the way, would there be much "passive" air exchange out the exterior vent w/o the inline fan on or maybe with just the canopy fans on?
Yeah, I had a feeling you'd have something to say about evaporation even when the lights are off.
By the way, would there be much "passive" air exchange out the exterior vent w/o the inline fan on or maybe with just the canopy fans on?
capncapo
New member
I'm sure that with ANY fan on you'll get a fair amont of air exchange. The greater the difference in temps., the better the flow. Canopy fans may be all that is needed at night.
If there is a HUGE temperature differential, you may get enough of a passive flow that no fan is necessary BUT you need to set the system up to take the greatest advantage of that. Your exhaust "stack" on the outside should be placed at least a few feet higher than the intake in order to get the airflow started and constantly moving in the right direction.
If there is a HUGE temperature differential, you may get enough of a passive flow that no fan is necessary BUT you need to set the system up to take the greatest advantage of that. Your exhaust "stack" on the outside should be placed at least a few feet higher than the intake in order to get the airflow started and constantly moving in the right direction.
causeofhim
New member
Interesting info. Thanks
reeflover2
New member
Just a quick follow up question. I just moved into a new home and am planning on building about a 12' by 14' fish room. I was planning on using vapour barrier on the inside of the studded walls and sealing this to the floor and using a external steel door to basically eliminate this room from the house. My furnace is a 90% efficieny furnance which does not have a pilot and is pvc vented in and out. I also had the builder install two 4" dryer vents and the room also has a window. I am building a 84" x 72" x 30" tank. Reading your posts I have figured (I think) that my furnace will not remove humidity during the heating in the winter months. Is this correct? Will it remove the humidity when the air conditioner is running in the summer months? My house also has a cold air return in the fish room already. It is the cheap carboard thermal stuff that they use here. Would keeping this cold air return available during the air conditioning season help remove humidity from the room instead of using fans with the dryer ducts? My thoughts are to use this method of control in the summer months and use the two dryer vents in the cooler and winter months to cool the room and control humidity. I was thinking of running one of the dryer vents down to the basement floor and the other one install a good sized bathroom fan in the roof. Does this make sense? Would you also have a supply vent in the room for the cooling season as well to supply cool air into the room? Would you put it at the floor as well? Ay other ideas?
capncapo
New member
Reeflover2,
The cold air return vent will help during the cooling season though I have reservations about the type of material from which it is made. The best advice that I can give you is to contact a local heating and cooling contractor and ask if there would be any problems associated with your vents and the humidity. My main concern would be mold growing on the inside of your return BUT I am not familiar enough with what you have to be certain about that. If it is what is commonly called "duct board", the material can develop mold in my environment in St. Louis but again, I am not aware of what possibilities exist when it is used in yours. How's that for a definite answer?
A supply vent would be a must if you are going to try to separate your fish room from the rest of your house.
Many 90% furnaces use the PVC in and out vents but many of the intake vents ARE NOT a requirement of the system and can be modified to pull the intake air from the home. You should be able to contact a local supplier of your particular furnace and ask them if the outside intake is in the design specs of the furnace and therefore is a must or if it can be converted to draw inside air. You will lose about 3% or 4% efficiency by doing this but you will also be sending some of your humidity down the drain as condensate.
Your 4" intake and exhaust vents should make a world of difference for you in the cooler and winter months.
As far as suggestions are concerned, I would need to know any information you can give me about your climate such as humidity levels in summer and anything else you think might help me.
The cold air return vent will help during the cooling season though I have reservations about the type of material from which it is made. The best advice that I can give you is to contact a local heating and cooling contractor and ask if there would be any problems associated with your vents and the humidity. My main concern would be mold growing on the inside of your return BUT I am not familiar enough with what you have to be certain about that. If it is what is commonly called "duct board", the material can develop mold in my environment in St. Louis but again, I am not aware of what possibilities exist when it is used in yours. How's that for a definite answer?
A supply vent would be a must if you are going to try to separate your fish room from the rest of your house.
Many 90% furnaces use the PVC in and out vents but many of the intake vents ARE NOT a requirement of the system and can be modified to pull the intake air from the home. You should be able to contact a local supplier of your particular furnace and ask them if the outside intake is in the design specs of the furnace and therefore is a must or if it can be converted to draw inside air. You will lose about 3% or 4% efficiency by doing this but you will also be sending some of your humidity down the drain as condensate.
Your 4" intake and exhaust vents should make a world of difference for you in the cooler and winter months.
As far as suggestions are concerned, I would need to know any information you can give me about your climate such as humidity levels in summer and anything else you think might help me.
Are you familiar with a venting product called "Humidex"? To me it looks like an exhuast fan built into a verticle rectangular duct attached to an outside wall. It draws stale basement air near the floor and exhaust higher up on the wall. With this principle in mind I was thinking of diy'ing something similar in my fishroom by installing a bathroom fan near the floor instead of the ceiling and exhausting about 5ft up the wall. Does this make sense? Also is there a simple test to check for negative pressure. My gas water heater is located in my fishroom. I plan to either install a grill/vent on the fishroom door to draw from the rest of the basement or if this is not enough, install a fresh air intake in the fishroom and then seal the fishroom off from the rest of the house. Any thoughts you have will be appreciated.
capncapo
New member
Hawk66,
I personally am not familiar with the Humidex product but fail to see the logic in its design. I would draw the air from the highest point possible as it is the warmest and therefore, most humid air in your fish room. I would think that removing the warmest, most moisture laden air would provide the greatest benefit when it comes to both temperature and humidity control. Removing the coolest air from near your floor will not help keep the wood in your floor joists or subfloor from absorbing the moisture contained in the hot humid air that will remain there.
A somewhat easy way to test for negative pressure would be to turn your fan on and hold something that produces smoke close to the flue pipe opening on your water heater. They draw air into the flue from the open space between the top of the heater and the flue pipe. If the smoke is blown away from the heater instead of being sucked up into ithe flue then you definitely have a negative pressure situation.
Personally, I think you would be ahead of the game by having the fresh air intake in your fish room and closing it off from the rest of the house. It will keep your house more comfortable in winter and will also help a bit with evaporation by reducing the temperature in your fish room. The cool air in the fish room can't hold as much moisture as the warm air from your house is capable of holding. I would place the intake as near to the floor as possible and the exhaust as near to the ceiling as possible. Not only will you be drawing the warmest air out but you may also reap some benefit from the natural convection.
I personally am not familiar with the Humidex product but fail to see the logic in its design. I would draw the air from the highest point possible as it is the warmest and therefore, most humid air in your fish room. I would think that removing the warmest, most moisture laden air would provide the greatest benefit when it comes to both temperature and humidity control. Removing the coolest air from near your floor will not help keep the wood in your floor joists or subfloor from absorbing the moisture contained in the hot humid air that will remain there.
A somewhat easy way to test for negative pressure would be to turn your fan on and hold something that produces smoke close to the flue pipe opening on your water heater. They draw air into the flue from the open space between the top of the heater and the flue pipe. If the smoke is blown away from the heater instead of being sucked up into ithe flue then you definitely have a negative pressure situation.
Personally, I think you would be ahead of the game by having the fresh air intake in your fish room and closing it off from the rest of the house. It will keep your house more comfortable in winter and will also help a bit with evaporation by reducing the temperature in your fish room. The cool air in the fish room can't hold as much moisture as the warm air from your house is capable of holding. I would place the intake as near to the floor as possible and the exhaust as near to the ceiling as possible. Not only will you be drawing the warmest air out but you may also reap some benefit from the natural convection.
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Capncapo, Makes sense, thanks for the info.
If your interested here is the link to the humidex site.
http://humidexatlantic.com/how_humidex_works
If your interested here is the link to the humidex site.
http://humidexatlantic.com/how_humidex_works
