Can be used to automate top-off or turn off pumps before they run dry. Includes float switch, solenoid and mounting bracket. $75. I'd consider trades trades or partial trades for frags, Apex Aquacontroller modules, an in-sump skimmer appropriate for a 42 gallon tank, welding supplies (especially an inert gas regulator or flowmeter), argon tank,or '66-'77 Bronco parts.
For more info:
http://www.lifereef.com/float.html
For more info:
http://www.lifereef.com/float.html