MH light or T5HO light

[jackp1]

basically I'm upscaling my orca tl450, iv kept tropical fish for years & now they have to go.. i need the tank for something a bit more interesting. right so first of my tropical, sorry ex tropical tank, is a bit larger than my little orca 450. its a typical rectangle tank 31+ half-inch lenght, 12inch wide 16inch high, its a tank + stand+ lid, integrated light, heater, internal filter, usual package bougtht it about 5yr ago fluval or other. anyway back to lights, well iv 2 options i can get, MH 150w clip on + the 20w light from the hood. or i can get the overtank GA T5-HO 4x 39w 90cm Adjustable hinged brackets to attach to the sides of your aquarium
* Inbuilt reflectors to maximize light output
* Splash guards to protect the tubes from water
* Reliable and efficient electronic ballasts instead of noisy magnetic ballasts
* Fully wired for use in British households
* Dual switches for separately switchable tubes (in banks of two)
* Pre-fitted with fluorescent tubes


so what do you think would be best, i want to be able to keep hard corals..cheers jack