my current tank is 24x24x18, 44g (45 depending on who you ask) so you're close. I've got a Coralife Aqualight Pro (150w) and from the last person who had it on the tank, there were a ton of possibilities.
I think the only problem with that shallow of a tank would be heat - You're running into dangerous territory come summer - My tank sometimes spikes as high as 82 - 84 if I'm not careful with the 150w
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