are those coins on the bottom of the tank? or are those snails? lol i can't tell...it looks dark. If its coins isn't it bad for the water where the fishes are in? Either way those are some NICE Gigas
xian leng is awesome man...that place has really amazing fish..the arapaimas r kept in a 28 foot by 14 foot pond that is about 6-7 feet deep
they look really fat, healthy and happy if u ask me...they coexist with a 5 foot paroon shark, small tomans and alligator gars...it might not be the biggest pond but they look fine..perfect colouration as well..