[scolley]

Originally Posted by BlueRam

I thougt the dosing pump does "top off" service.

Not for me... and my hat's off to people trying to make that work. My evaporation rate is way to inconsistent for me to try that. All depends on the heat, and that varies significantly.

Originally Posted by BlueRam

You might be able to rig somethink like this in the cypress stump:
http://www.bluelineaquatics.com/products/topoff_system/

Seen those. Thanks! What I'm trying to do now is quite similar, except I've got a water pressure sensor at the bottom of a tube that passes through the bottom of the tank, rather than something over the top with an air pressure sensing on top. I suppose if I had set it up initially, I could get one of those bulkhead airline connectors to make that work. But messing with bulkheads now means tearing down the tank. Not an option for a year or so.

Originally Posted by BlueRam

My sink is lower than my tank, so I use* the python to start and then turn off the tap and let it go.

Not an option for me I'm afraid... sink's too high.

Originally Posted by BlueRam

Very expensive example:
http://www.kc-denmark.dk/public_html...altic_pump.htm

Yeah, massively expensive! The dual perstaltic idea makes me uncomfortable, due to the "some of the water that just went in a second ago, is in the water going out now" problem. Kind of clouds the question of just how much turnover you are really seeing.



Thanks for the ideas though. Any ideas on how to get what I've got workind? How to get beyond that 10" of water state-cycling problem?