From what I read and from personal experience, normal bluye and white light is sufficient for a tank with a depth of less tha 2 feet (60cm). Sorry I don't know how to tell the difference between a PL and VHO. I've seen some Arcadia tubes in the shops sell for around RM50 (3feet). I'm not sure if they are VHO bulbs but they seem to have the correct light temperature.

Anyone out there can add more info?