You get what you pay for... but here it is:
12v 1 amp switching power supply
http://www.ebay.com/itm/New-Black-DC...-/191210306026
12v 3 meter lift pump
http://www.ebay.com/itm/DC-12V-3M-Br...p/251990373545
12v relay
http://www.ebay.com/itm/RELAY-5-WIRE...-/261983427835
2 float switches
http://www.ebay.com/itm/2PCS-Horizon...-/321956345652
10 feet food grade 5/16 id tubing
http://www.ebay.com/itm/1-X-Vinyl-Tu...-/301863077584
power supply 4.99
pump 5.77 + 0.99
relay 4.90
float switches 5.59
tubing 7.62
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total 29.86
The idea is one float switch turns on the pump, while an upper float switch is on when not floating, and will interrupt the lower switch when it floats. This is to prevent overflows if the lower float gets stuck down. I would be careful with this, I am thinking of using it on the 3 gallon pico contest where an overflow won't cause damage because my ato reservoir is going to be 1 gallon but I wouldn't use it for anything expensive or important