3m is 10ft so that gives you 20ft total. All I have to do is get more of the same wire from tunze, unsolder the floats, solder in an extension and add solder the floats back to the extension and use shrink wrap. You could do it but it would have no warranty, if I do it you keep your warranty. Just order it and specify the custom length cables from a dealer. It will take about 4 weeks as I need a couple weeks to get the cable.