It was a second hand tank but it looks like the t5 unit was disconnected so I could always look for a replacement unit. Are t5’s ok for corals and still low voltage? Saying that tho, a replacement unit seems to be quite expensive so are there any suggestions of an cheap light to back up my Fluval one ?
T5's will grow Corals and grow them well. It depends on the look you like. I'd run it 3 Aquablue and one actinic T5 Bulb.
T5's typically are around the 15-16K colour temp mark, LEDS these days seem to run in the 20k region. The T5's generally are not as blue
How cheap we talking? 18W Par38 Bulb with Gooseneck would set you back about £45, 168W Luxbird (Chinese Black Box) £90.00 plus you'd need hanging or mounting kit.