Very Simple Gravity Style Auto Top Off System

[bbyatv]

I stole this idea from some place on the web and made some modifications so that it would work.

I have been using it for 5 weeks and it works perfectly.

Here is the general idea:



To build and use this gravity style auto top off system.

You will need the following materials:

1. A 4 litter wine bottle.
2. About 10 or so feet of air line tubing
3. Silicone sealant
4. An air line valve. (I used one that came with a power head for the venturi)
5. An 18" long piece of 1/2" PVC
6. An 1/2" PVC pipe cap
7. 8 inches of hard air line that will just squeeze inside the air line tubing


1. Take the wine bottle and drill 3 holes in the cap that are just a hair smaller that the air line you will use.
2. Feed/squeeze three pieces of air line tubing through the 3 holes in the cap
3. Make the tubing long is enough to reach the sump from where you will keep the wine bottle.
4. Cut 3 pieces of 2 inch long hard air line and force them up into the air line tubing from the inside of the cap.
(This will make a nice tight seal between the air line tubing and the cap as shown below)



5. Seal the 3 tubes and cap with some silicone sealant.
6. Add a piece of air line tubing that will reach the bottom of the bottle to the end of the hard air line that flows water to the sump.
6. Drill a hole in the PVC cap just big enough to force the end of the air line tubing through it.
7. Force a 2 inch piece of hard air line up into the air line tubing to create a tight fit with the cap.
(Just like the wine bottle cap)
8. Silicone the outside of the cap and tubing.
9. Cement the PVC cap on to the end of the 1/2" PVC tube.

To use the set up.

1. Mount the PVC tube above the sump in some way so that the tube is fixed and can not move. The end of the tube that is in the sump will determine the water level in the sump. So to adjust the water higher, move the tube up.
2. Fill the bottle with DI water.
3. Place the cap on the bottle and make sure it is tight.
4. Place the bottle so that it is higher than the sump. (Gravity works!)
5. Open the valve on the air line tubing.
6. Suck on the tubing that will flow the make up water down to the sump and get a siphon started.
7. Stick the end of the tubing you just started the siphon in into the sump area where the PVC tube is located. The end of this siphon line needs to be in the water. This prevents air from going back up the tube and killing the siphon.
8. Close the valve on the air line tubing.
9. Water will run from the bottle into the sump until the water level reaches the botom of the PVC tube and creates a hydaulic lock on the siphon.
10. When the water evaporates from your tank the water level in the sump will drop below the end of the PVC tube and allow air into the water bottle allowing the siphon to start again and water will flow into the sump until the level once again reaches the PVC tubing.

Here are some pics:







If you have any questions let me know.

Bruce

[t-bone2]

good engineering but i will stick to my even more simple 5 gal iv drip top off

[bbyatv]

Can you post some pictures or sketches?

Bruce

[shyland83]

even better, i would use a 6 gallon wine jug with a rubber stopper in the top. can get one online or at any wine making supply for about 30 bucks.

[MrRyanT]

Great idea!! Thanks for sharing!

[rickh]

Originally posted by t-bone2
good engineering but i will stick to my even more simple 5 gal iv drip top off

This method will work, but the amount of water added has no relationship to the amount of water needed to bring the level back. You set it and hope the evaporation rate stays constant. R

[spooda420]

OMG good thing you can type, I cant read those CAD drawing very well

[bbyatv]

Originally posted by rickh
This method will work, but the amount of water added has no relationship to the amount of water needed to bring the level back. You set it and hope the evaporation rate stays constant. R

You are not understanding the way this works. The only time water is added is when water evaportes. This sysrem keepts the volume in the tank very exact. It works very well and keeps the salintiy perfect.

Bruce

[MMM33732]

I've seen this setup a few times before, but never with a valve... Whats the valve for? To get the original siphon started? If so, the only time it should need refilled is once its empty right?.. so then there shouldn't be any water blocking the vac line/pvc as long as the sump water level is just a hair below that... So then you wouldn't really need another way for air to enter the holding container since that would allow air in until the sump level reached it again which would happen as soon as you start the siphon again and the sump level raised up a touch.

[rickh]

Originally posted by bbyatv
You are not understanding the way this works. The only time water is added is when water evaportes. This sysrem keepts the volume in the tank very exact. It works very well and keeps the salintiy perfect.

Bruce

I see how your method works. It's the IV drip method that I was referring to.
The IV just drips at hopefully a constant rate, independently of the rate of evaporation. R

[bbyatv]

Ahhh. I got ya. Ya, I have run a drip before and that is a problem. Plus as the volume of water goes down the drip seems to slow. All and all, I am not fond of the drip scheme.

Bruce

Originally posted by rickh
I see how your method works. It's the IV drip method that I was referring to.
The IV just drips at hopefully a constant rate, independently of the rate of evaporation. R

[t-bone2]

works like a champ not bashing your way at all just to much cluter for me like i said good engineering

[Malifluous]

Why do u need the PVC tube? Can just airline be used to create the hydraulic block? Do u need the larger diameter of the PVC?

[bbyatv]

That is the change I made to the system I stole. If you just use an air line water gets sucked up the air line when the water level reaches it. The weight of the water wanting to run down into the refugium is enough to pull water up the air line. With the large diameter PVC it prevents that from happening.

Bruce

Originally posted by Malifluous
Why do u need the PVC tube? Can just airline be used to create the hydraulic block? Do u need the larger diameter of the PVC?