Look at my signature for inhabitants. My 18.5gal has almost 1W/gal (15W) and my 28.5 has 0.6 W/gal (18W). So you can keep plants with low light. The smaller plants in my 28.5 are cuttings, not badly growing (Not meaning the Java fern or the other plant on my driftwood and in the front.) I'll post another pic in 2 weeks to give you guys a comparrison.