QUOTE (timdanger @ Aug 26 2009, 09:07 AM)

I personally am not a huge fan of drilling a bunch of holes in weight-bearing supports. i'd rather have all the support i can get. there is a *lot* of weight in that tank (i'd estimate 600lbs, with live rock/sand/salt water/thick glass), and because it's a cube, it's got more weight per square inch of footprint than a rectangular/long tank would have (where the weight is distributed over a wider area, thus putting less stress on the square inches of space underneath the tank).
having said that, i err on the side of caution with that stuff. and i'm not an engineer, and wouldn't be able to provide calculations on how much our stand's sawdust-walls can support to convince myself that this type of thing isn't risky. and, just because someone else's hasn't failed doesn't mean it's structurally sound (again though, i'm not an engineer). at the end of the day, the best reason not to drill the hole is because you don't want to void your warranty in case something goes wrong. e.g., you drill the hole, your wall gives just a little (so little that you don't notice), your tank is no longer supported on an even plane, the seams of your tank come apart or your glass cracks.....). but, like i said, i am overly cautious.
as far as the equipment in the cabinet being a problem, i have seen several people do it in other threads (installing power strips/controllers/etc.). again, i'm not sure i would do it myself, but i don't have hard data to back up my theory. my theory is just that you've got equipment running (causing evaporation), you've got potential splashing/dripping, potential salt creep, and you've got a fan running in the sump for evaporative cooling, all in a relatively enclosed/unventilated environment. and, that humidity is going to rise. i know the RKL is obviously "aquarium equipment," but i just don't see that it would have been designed to be run in a high humidity environment like that. i think a good example of the downside is the stock fuge light -- lots of people over on reefcentral had their fuge light rust. again, no real facts to back this up -- i just don't see it as being a good idea, especially when it can just as easily be mounted to the outside of the cabinet as the inside.
Tim,
Thanks for that reply. As far as load, this is how I computed the weight of everything:
Tank = 40lbs
Lights = 20lbs
LR = 50Lbs
LS = 40Lbs
Salt = 50Lbs
Fish, Corals & Inverts = negligable
Water = 39G x 8.5 = 321.5
Total weight load on Cabinet = 541Lbs Approx
I understand your caution. Since there are already 2 holes in the back of the cabinet I could put the vent on the right side panel right next to the cooling fan. From what I have seen in almost all of the Cad Pro tanks I have read is they keep most of the electrical inside the sump area and I haven't heard any issues with that yet. I would just suggest doing a really good cleaning job once a month or so. Or maybe I'll throw some baking soda in there

I will probably keep a good eye on the sump for a while and if it seems necessary, then I will add the extra ventilation.