I have a 10 gallon tank with six guppies and 5 ghost shrimps. it has a filter, 15 live plants planted along the back, a half tube type thing in the middle with plants growing off of it as well, a rock with an arch in the corner, and a water heater. My question is, how do I vacuum the sand without sucking up any ghost shrimps? there is a little waste from the guppies on the sand, and I think the ghost shrimps just fill up on guppy food. tia -Kady