I think the leds might be overkill to be honest. I have a taotronics unit over my 60g which is 2 feet deep.
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light units. For that tank I believe you can get a 4 bulb t5 system with timer for around $100. I think the 24" model is only $89 on ebay as well.
You could always get the adjustable led
's but then theres the issue of how to mount them over the tank. You cant just drop the fixture on a glass cover, I have mine hanging over my 60g with two large bars attached to the back of the stand. Also, with a sw
tank you would want to skip the glass tops as well to aid in the gas exchange.
I have tried every single lighting setup and still fallback to t5's alot, they can be a tad more expensive over the long run as you have to replace bulbs every year or so and they cost a bit more to run electricity wise. You can't beat the shimmer you get from led
's tho, but I'm thinking it';s a personal preference