Another observation on fishes.

Current Lighting Regime
Light is on from 5:00 PM til 1:00 AM. Total of 8 hours for MH. Reason is because I want to view the fish when I am back home.

Observation is from 8:00 PM til light off - MH
1) Bleeding Heart hides under shadow. I tested switching off light and immediately saw them swim out and become active.
2) Boraras same but not so bad. At least they are more in the open.
3) Gold Tetra, swim about all the time.

Previous Observation is from 8:00 PM til light off - PL36X4
1) Bleeding Heart swims around at the front bottom very actively.
2) Boraras swim at the back middle very actively.
3) Gold Tetra - haven't put in yet at that time.

Possible Reason
Fish is thinking it is afternoon. Time for afternoon nap.
Light too bright and fish is afraid.
Most fish except boraras is 1 1/2 weeks old in new tank. Maybe still shy to new light and environment.

Possible Solution
Setup morning -> afternoon -> evening lighting cycle like what Dom suggested.