I bought a terrific unit from Wings and Wheels. It is avaialble in
liters, resettable and compact. The addition of some PVC fittings
gave me a garden hose connection with a shut off, and on the outgoing
side a 'T' fitting provides a standpipe to prevent overfilling
damage. Yo0u can see it midway down the page at http://www.wingsandwheels.com/page45.htm
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