Or just keep 1 net per tank, as for food, I just thaw a portion out in a measuring cup (thats just used for feeding my fish) and use my fingers to portion out their food.
I do some aquatic sampling for work; we use a 1:1 solution of Chlorox and water to disinfect equipment between sites. Soak the net in the bleach solution for a minute or two, then allow to air dry. The bleach will evaporate out. You don't need much solution; just mix a little in a plastic baggie big enough to hold the net.