300 gallon dd system/ humidity
- Thread starter cr85r
- Start date
sfsuphysics
Active member
it all depends upon how much water gets evaporated. If you evaporate a couple gallons a day, that's a couple gallons that went into the air and around the room. More than likely condensing on any cold surfaces (windows) but also absorbed into the walls. Mold is the largest issue that you need to worry about IMO.
I would usually suggest a vent to pull air out (replaced by dryer air from elsewhere), but that is a large room. A dehumidifier might work better too, if it's a room that typically has good airflow through it (i.e. windows, doors, etc), but they tend to use quite a bit of electricity.
I would usually suggest a vent to pull air out (replaced by dryer air from elsewhere), but that is a large room. A dehumidifier might work better too, if it's a room that typically has good airflow through it (i.e. windows, doors, etc), but they tend to use quite a bit of electricity.
prop-frags
SPS Slave
+1
Ask a good HVAC expert. The humidity from any source needs to be pulled out, or it will go somewhere. Depending on the climate you live in, and your tolerance for comfort (i.e., relative humidity and temp in your home, the capacity of your home's AC unit may be overwhelmed by even a smaller aquarium, especially if you rely upon evaporation cooling versus a chiller.
If you're planning on having the whole 450g setup in a single room, you really should look into a supplemental Air Exchanger, ERV, or similar solution.
thelizardkin
New member
I have a 420g in my house and I have no problems with humidity but the room it's in is about 10 degrees hotter than the rest of my house
slief
RC Sponsor
I have a 480G display with about 550G of total volume. I have a 10" axial fan that sucks the air out of the sofet above the tank and vents it to the outside of the house through an air duct. That same fan also pulls air through a void in the curtain wall along one side from below the tank. In 14 years of my tank being up at this house, I don't have humidity problems.
My tank is a 3 side display and completely enclosed from top to bottom. The fresh air gets into the sump are as well as the light sofet from the edges of the access doors. My sumps also have covers on them so the humidity below the tank is pretty low on its own. Above the tank I have a pair of 24"x24" openings.
This is how my duct fan is setup
A view of the duct
The vent on the outside of the house
My tank is a 3 side display and completely enclosed from top to bottom. The fresh air gets into the sump are as well as the light sofet from the edges of the access doors. My sumps also have covers on them so the humidity below the tank is pretty low on its own. Above the tank I have a pair of 24"x24" openings.
This is how my duct fan is setup
A view of the duct
The vent on the outside of the house
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kalgra
New member
Do you run the vent fan all the time or do you run it on a timer or humidity controller? Also if you do run it with a controller what humidity level to you have it set at?
Second question, and please excuse my ignorance here. Are humidity issues generally more prominent in arid climates or wetter climates? Logic tells me a dryer region would yield higher evaporation but I don't know that to be fact.
slief
RC Sponsor
I live in a drier region but humidity can be an issue anywhere depending on the amount of evaporation and the ventilation.
For years I ran my fan only when the lights were on. Its was primarly for keeping the tank temps managable when my halides were on but its also removed any humid air. I have since swapped my halides for LED's and now run my fan 24x7 in an effort to help reduce tank temperatures both above and below the tank as I was trying to reduce the need for my chiller. Since my pumps, uv lights and my fuge are below my tank, I figured keeping it on 24x7 would be best as the fuge lights come on at night and the pumps tend to heat the air down below the tank as well. The end result is less humidity, less heat and my chiller hasn't run in weeks.
kalgra
New member
Thanks was just curious as I’m in the middle a my first build a 200g in wall display and 125g sump in a small dedicated room in the basement about 300 as well. I live in a very dry climate so not real sure what to expect yet. However, I did already install a fan and vent for both the display and the room the sump is in along with a dehumidifier (which I’m not sure I will use). Just curious if I should be running the fans 24/7 or just if temp/humidity hit certain levels. Not concerned about temp problems at all as I'm going all AI LEDs but humidity is certainly a worry I have especially in the winter months.
The windows in my house suck! And I don’t currently have 20k to get new ones. When I got a whole house humidifier installed with a new HVAC system it was great until It started getting really cold then what happened was the moisture condensed on the cold windows formed water droplets which then froze to the window frames. When the sun would come out the ice around the windows would melt and caused warping and other water damage to the windowsills and wood floors below. I have not run the humidifier since.
cr85r sorry for the hijack.
My questions seemed to be in line with yours hope that was ok.
The windows in my house suck! And I don’t currently have 20k to get new ones. When I got a whole house humidifier installed with a new HVAC system it was great until It started getting really cold then what happened was the moisture condensed on the cold windows formed water droplets which then froze to the window frames. When the sun would come out the ice around the windows would melt and caused warping and other water damage to the windowsills and wood floors below. I have not run the humidifier since.
cr85r sorry for the hijack.
My questions seemed to be in line with yours hope that was ok.
Kerreefer
In Memoriam
*HVAC tech...*
5 ton ac system can pull up to 10-15 gallons per 24 hours. the biggest calculation to it is wet bulb, coil temp, run time, fin surface area. super high efficient (20+ SEER rating "minisplits) can pull out more humidity per btuh than an old 8-10 SEER central unit. plus cost WAY less to run.
one of the systems i oversaw during installation on a school pulled out 800 gallons of condensate per 24 hours on a humid day heheh.
5 ton ac system can pull up to 10-15 gallons per 24 hours. the biggest calculation to it is wet bulb, coil temp, run time, fin surface area. super high efficient (20+ SEER rating "minisplits) can pull out more humidity per btuh than an old 8-10 SEER central unit. plus cost WAY less to run.
one of the systems i oversaw during installation on a school pulled out 800 gallons of condensate per 24 hours on a humid day heheh.
Kerreefer
In Memoriam
yup, but the only issue that i know of on those are parts are a pita to get and they are a Bi@# to work on. well all minisplits are, but yeah.
most of them use dc driven cmpressors to achieve superhigh effeciencies, therefor you have a TON of electronics for ramping and controlls. once its on you will never know its running. they are Superiorly quiet!
now on one note: saltwater evap. w/in 10-12 feet of the evaporating coil will in time ruin it. i understand that salt itself does not evap. BUT ive changed out 2 returns on my unit due to it being 6-8 feet from the tank. it WAS low to the floor (return), so im not sure if that played a factor. anyhow i moved the return to the ceiling and on the other side of the room, and not a single bit of rust on this grill now.
most of them use dc driven cmpressors to achieve superhigh effeciencies, therefor you have a TON of electronics for ramping and controlls. once its on you will never know its running. they are Superiorly quiet!
now on one note: saltwater evap. w/in 10-12 feet of the evaporating coil will in time ruin it. i understand that salt itself does not evap. BUT ive changed out 2 returns on my unit due to it being 6-8 feet from the tank. it WAS low to the floor (return), so im not sure if that played a factor. anyhow i moved the return to the ceiling and on the other side of the room, and not a single bit of rust on this grill now.
Kerreefer
In Memoriam
out there i wuld wait and see how it goes first. minisplits are expensive and if you really didnt need it then yu have a new minsplit installed and never use it heheh. a much cheaper approach if you dont mind the asthetics (some people hate it) would be a window unit. way cheaper and can be framed into a wall instead of a window (more asthetically pleasing over stuffed in a window).
Sanyo mini split
Sanyo mini split
I'm getting a mini split for mine in two weeks. They'll put one unit in the main part of the finished basement for cooling and minor humidity control and the other unit in my L shaped fish room where I have combined water volume of 700 gallons. I was told it has great humidity control. 4 liters/hr water removal 24000btu total
Currently I have a 1350cfm attic fan mounted vertically in my wall, vented outside that's on a timer (4x day). There's also a 12000btu window air conditioner in that room, but it's an electricity eater. Both of these still don't keep the humidity under control in the summer so I had to fork out the cash for the mini split. I'm hoping to someday take my chillers offline too.
Sanyo mini split
I'm getting a mini split for mine in two weeks. They'll put one unit in the main part of the finished basement for cooling and minor humidity control and the other unit in my L shaped fish room where I have combined water volume of 700 gallons. I was told it has great humidity control. 4 liters/hr water removal 24000btu total
Currently I have a 1350cfm attic fan mounted vertically in my wall, vented outside that's on a timer (4x day). There's also a 12000btu window air conditioner in that room, but it's an electricity eater. Both of these still don't keep the humidity under control in the summer so I had to fork out the cash for the mini split. I'm hoping to someday take my chillers offline too.
