อ่านเลย ...
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Do the fish swim to the front of the tank?
Do they feed aggressively?
Do they look fat & in shape?
Do the eyes look clear and bright?
Do the fins are straight & tall upright?
Do they breathing normally?
Is the tank housing the young Discus clean and the water clear?
1. Dark color (Blackish). Possibility of sickness.
2. Heavy breathing (except when they feed & tank not aerated properly).
3. Non active.
4. When breathing only one side gill is working.
5. Hormoned discus (some breeder hormone fish to develop color).
6. Eyes looks big (possibe, fish is stunted)