so sorrry phoenix i hope your still about only read your post today. I will try to answer the two questions raised. The 620 has 2 x 18 w pc lighting. Could do with a bit of an upgrade but will do for low light corals. I havnt yet tinkered about behind the lights but i think it would be slightly difficult to re locate it because it is directly under the bubls but i think it could be done. I honestly dont think theres enough room to put more bubls under the plastic thing so what would have to be done is the light bulb holders moved over, remove the plastic thing , fit new bubls next to the old then get an acrylic sheet and fit it over. Now to the second question ooh i never knew that gap was for an auto feeder lol. I think maybe what you could do is in the over head filter is fit a bulkhead into that to create a drilled drain. that way no drilling of glass. but ithink you could do a syphon youd just have to mod the hood alot