Hi Diana, I am just starting. Want to start one in my living room. Looking at doing a 40 to 60 gallon tank. I have ordered my water and air pump and led grow light. I just have to go to agway to get my fish tank and grow bed. I agree gold fish might be good to start with. I am so excited about getting one started. However I don't know if I will be able to grow the vegetables I want in such a small system. I really like your ghost koi. How big do they get?