No problem. I have to drain my Whotes tank at least every two weeks.

I also put in a gravel section on one of my art tanks to create a small water area but also so I can siphon excess water from the tank when it gets higher than the hydroballs.
With the gravel setup up you need to have screen material between the hydroballs and the gravel since the hydroballs like to move and mix with just about anything :-)