I would bother with LED for a tank this size, it will cost a fortune and require extensive modifications to the existing hood.
These LED lights are brighter than T5 and fit in T5 tube holders. Aqualantis LED
But you will have to modify your hood ie open the sealed Juwel lighting unit to wire these in as well as costing £180 each.
I have a 4 tube set of these for my Vision 180. Work brilliantly. Bought in 2015, still going fine, two of the tubes are still original "colour tubes" still very bright. Recently bought new reflective strips as they do scale up/loosing reflectiveness after a couple of years. iQuatics T5 units.
These are/will be very bright lights, with 4 tubes, just make sure your CO2, ferts and flow are spot on or else you will be vapourising plants and growing algae.