It's certainly doable as long as you can do a gravity drain system. The only downside is you will need to drill your tank. You can set up a drip system to constantly stream water into your tank and then have the water continually gravity drain wherever it needs to go.
You can get by without drilling your tank, but you're risking a flood.
"The simplest explanation for some phenomenon is more likely to be accurate than more complicated explanations." -Occam's razor