Colin_P
Guru
I’ve found that a single run of LED tape under the units is generally enough.
I’ve been using this https://www.amazon.co.uk/gp/product/B00JQV6SFU (warm white) and this https://www.amazon.co.uk/gp/product/B00JQV6U7Q (daylight white), which is around 12-13 pounds for a 5m length.
I've done this, they've been in a few years now without issue also as a replacement of those old fashioned slim fluro tube units which only lasted a few months.
I have a two strips (for better light distribution) of 3528 leds in warm white, brilliant. With a bit of research you can work out the wattage of the transformer(s) you need. A very cost effective solution if you buy the strip and transformers. When I did this there were brighter 5050 leds available and so I believe even brighter ones these days.