I'm keeping my L Klugi sling in a 3 gallon with about 4" of substrate. I moved my scorp to the new 5 gallon tank I purchased. As long as they can find food and stay out of trouble, going a little large is ok. My T in the 3 gallon basically stays inside of her skull all of the time, making the rest unimportant. I just drop crickets into the nasal cavity. Plus rehousing gets to be stressful and expensive. In nature, they don't live in deli cups.