I must point out that it really depends on what LEDs you use, high-watt LEDs are generally high-lumen but they are also generally more expensive.
If you're just using them for lighting fish then it doesn't really matter what watt/lumen they are just as long as you can see the fish
A LED strip for plants(6,500K) was $120 USD or something in that range, the guy selling them told me I would need two for my 60cm x 30cm and 3 if I wanted to grow high-lite plants(glosso etc). LEDs are more beneficial in marine setups due to the lower heat output and matched efficiency of MH lamps, along with the much coveted 'shimmer' effect.