Hi Adrian,
Sort the following three issues and you should be ok.
Light -
A big one this. You do have a lot of light, 2wpg HO T5 is high-light. I recommend running just 2x54w for 9 hours straight with a midday burst (all 4x54w) for 3 hours, so 3-3-3. You'll need two plug-in-timers, of...