They are beautiful fish but lots of work. IMO, worth it. As the fish matures it will stay out a lot more than it is. After 5+ years ours was always out and about during the day. Our mandarin love reef nutrition roe, mysis feast, tigger pods. LRS reef frenzy for frozen and TDO chroma boost for pellets. These foods were fed multiple times a day and we still had to dose pods monthly. There metabolism is fast so even if you get the mandarin to eat other foods, pods should always be added. I honestly don't think a smaller tank is better. The large tank will have a lot more area for the mandarin to graze at and ultimately have more area for large pod populations. Feeding phyto to feed the pods is an excellent suggestion.