As the tank is cycling does this mean you have a dusty covering on the sand surface? if so then this is merely diatoms and completely natural for a maturing tank. I would not take it out as it will onll return. It needs to run its cycle to get rid of the silicates thats living wihin the sand and water colum. Might take a few weeks and then of course you will get the red cyano but again this is a natural part of maturing.
Also, I would not start taking water out of the tank whilst its cycling. This will only lengthen the cycle and thus makeit longer to introduce fish. Just let the tank run its course, it will look a bit messy for a while but this is just part of the process )