Would this compact auto top off system work well?>

[mike31154]

I've set up the carboy/air pump rig on my system & it works well, although I've found that as the water level goes down in the carboy, the flow is also dropping. Could be because my stopper is not sealing perfectly. I had to use a glue gun to fill the hole in the center of the stopper since I've been unable to get hold of a solid stopper. But I'm inclined to think the main reason is due to the drop in water level in the carboy - more volume of air needs to be pressurized.

This is fine for when I'm at home since I can manually run the air pump longer or put the carboy up a little higher to compensate. Not sure I would trust it for more than 4 to 5 days unattended though. I have a timer set up to pump for 5 minutes 4 times in 24 hrs and that was keeping the DT topped up nicely until the level in the container dropped to half. That's when I upped the timing to 10 minutes on one of the cycles and also put the carboy up on an inverted salt bucket.

I think once I get a sump set up, I'd like to use a similar system but instead of using a timer, I'd be inclined to take things a step further and use a float switch contolling a relay to run the air pump. Nevertheless, I like the the simplicity of the current set up and it sure beats topping up manually with a 1 gallon ice cream bucket.