mogie
Well-Known Member
Contributed by: Ranger2000
This FAQ entry offers a way to make a device that can maintain the water level in your hydro reservoir or humidity cup. It is gravity powered and made from stuff you can get at your local home maintenance store. There are no moving parts other than water. I have built this and it does work. Sorry, I do not have a digicam to submit pictures.
I have been using this for the last 3 months to keep a constant level in my humidity water within the grow room. It works like a champ, keeping the level to within 1/16 inch of where I set it at all times. I used to fill the cup every day, now I just replace the water bottle when it is almost empty. I found that I was using about 2 liters per week during the winter while in veg mode (150W HPS). Now that spring is here and ambient humidity has risen, I have entered the flowering stage and water consumption has slowed to about 2 liters every 3 weeks.
For those doing hydroponics, this is an alternative method to maintain your reservoir level if you go on vacation. Past methods I have seen involve float switches or valves. This technique may remove some of that complexity for people who don't have easy access to those items.
The technique is scalable. I have used it with 2 liter soda bottles, but you can easily use a 5 gallon carboy for holding the extra water. The only key requirements are that the bottle holding extra water can be totally sealed against any atmospheric air leaking in around the edges and it must have walls that are stiff enough to withstand a bit of negative pressure. The pressure comes from the column of water and is equal to about 1/2 psi for every 14 inches of height difference between the bottle and the reservoir top. A 2 liter soda bottle can handle about 2 feet of difference (1 psi). A carboy has thicker walls and can be mounted much higher. Sorry, plastic bags of water won't work.
Construction Information
Here is a diagram that explains how to build the device.
This FAQ entry offers a way to make a device that can maintain the water level in your hydro reservoir or humidity cup. It is gravity powered and made from stuff you can get at your local home maintenance store. There are no moving parts other than water. I have built this and it does work. Sorry, I do not have a digicam to submit pictures.
I have been using this for the last 3 months to keep a constant level in my humidity water within the grow room. It works like a champ, keeping the level to within 1/16 inch of where I set it at all times. I used to fill the cup every day, now I just replace the water bottle when it is almost empty. I found that I was using about 2 liters per week during the winter while in veg mode (150W HPS). Now that spring is here and ambient humidity has risen, I have entered the flowering stage and water consumption has slowed to about 2 liters every 3 weeks.
For those doing hydroponics, this is an alternative method to maintain your reservoir level if you go on vacation. Past methods I have seen involve float switches or valves. This technique may remove some of that complexity for people who don't have easy access to those items.
The technique is scalable. I have used it with 2 liter soda bottles, but you can easily use a 5 gallon carboy for holding the extra water. The only key requirements are that the bottle holding extra water can be totally sealed against any atmospheric air leaking in around the edges and it must have walls that are stiff enough to withstand a bit of negative pressure. The pressure comes from the column of water and is equal to about 1/2 psi for every 14 inches of height difference between the bottle and the reservoir top. A 2 liter soda bottle can handle about 2 feet of difference (1 psi). A carboy has thicker walls and can be mounted much higher. Sorry, plastic bags of water won't work.
Construction Information
Here is a diagram that explains how to build the device.