as I've read Mandarins need extensive rockwork because they feed off the rocks and need hiding places. Currently my tank, which is a 30g, has about 20lbs of LR. I knew it needed more before I got the mandarin, but now I NEED more. Since the Mandarin feeds off the rock should I but more LR or can I buy base rock? Base seems cheaper and I'll all for cheaper but i want what's best for the tank/Mandarin.