Thanks Alan, more good advise.These larger breeding traps, would they be made with two end pieces of glass and another two pieces glued to form a V between the two ends , with a match stick gap at the base. If so , for a 600 x 300 x 300 tank, trap height of 290 , width of 290, and side panels of 290x290 would leave a good gap under trap for fry to drop through. How do these dimensions sound? Let me know if you think I should be going longer. I like the sound of bigger traps as the bought ones are far too small and stressful. On the room front I have tracked down some coreflute to line the walls with. As for your 12 volt night light system, I am dead keen on LEDs so will try hooking up a small solar system, I like the fact that bbs will be attracted to them. Thanks Alan a few more things are coming together, will order glass next week after your feedback. Regards Mark.