Every one is different! "Koi" is a very exciting morph, because it presents endless possibilities. This variety also breeds well, and appears tolerant of both humid and dry (but not excessively dry) conditions. We give ours wood and limestone for cover, as well as a corner of the habitat with damp moss. They also like protein, and could potentially harm smaller species of frog and salamander in bioactive setups. They will do great with larger species, though.