I'm planing on getting some Hermit Crabs to put in my 10 gallon glass tank. The tank has a wire lid/roof. Now the questions: 1.How many crabs can I put in the tank? 2.How big of a water dish should I use? 3.How many sponges should I put in the water? 4.How big of a food dish should I use? 5.What's the best food to buy? 6.What kind of material should I put on the tank floor? 7.What kind of items do the crabs need in the tank? 8.How deep should I put the material on the tank floor? 9.How many extra shells should I keep in the tank? 10. And finally, how active are the crabs?