Definitely go with a sump on that. What size are the holes in the overflow? I would think it would suit a Herbie style piping or two in the overflow and then use the two in the tank as short outlets with check valves
The 2 holes in the middle of the tank are 1-3/4" dia. The 2 small ones in the overflow are 1-3/4" dia and the big ones are 2-1/4" dia.
Not a weird drilling at all. Do you know where your boss got the tank? My bet would be a salt water place. To get more flow, salties often have more holes drilled where the live rock piles will be so that they can hook up extra pumps to increase flow for the corals. One hole for intake and one hole for output with no filter just a pump.
Also regarding the four holes in the over flow, it's safer to have four small over flows than one large one in case an anemone moves into the overflow and blocks one of the pipes.
I'd go for the sump if the office can stand some noise (which can be minimized with a herbie standpipe.)
If the office is a real quiet place with people bothered by noise, I'd go with a large canister.
Thanks for the explanation there! We like our quietness but I'll look into the herbie standpipe. I just found out there was 2 Oceanic Systems Overflow Accessory Kits hiding somewhere. And it looks like it was made for a herbie style overflow! Which would explain the 2 return and 2 drain holes in the overflow.
If you plumb those bottom holes in the middle of the tank as a closed loop there is no need for check valves. I would think the holes in the bottom of the tank would be useful for a closed loop going to a CO2 reactor if you are planting the tank. Or just put a closed loop for circulation or cap them - if you don't need them you don't need them. That does sound like it could work for water changes too, with a valve and a T attached to a hose between the pump powering the closed loop and the tank you can fill and empty the tank rapidly. Perhaps that is the main reason the holes are there. I haven't done this, emptying sounds fine but filling seems like it wouldn't work through the bottom holes.
Is it going to be a planted tank?
Who gets to go scuba diving to maintain this monster?
What about a big school of corys or hatchetfish as well as discus and smaller schooling fish? Tank is going to be covered, right?
Sounds like a plan to use to 2 middle ones connected to a shut off valve for quick tank draining.
Planted? Hopefully if I can get plants that are easy to maintain. Probably NLJF and the likes. Boss still needs to be sold on this though.
Plug the 4 small holes in the actual overflow. Use 2 of the remaining for large holes as intakes ( probably the back 2) and then the other 2 as the return (you have a return line bulkhead already setup. (That's the hole below the slots or weir).
Sounds like a plan!
With a tank that tall I would use all low light plants, with CO2 and high light, a big sump with a high flow rate pump. I would use wood so you can put java trident etc, between splintered areas.
Now I get to plan this out with all this information.
Work is more fun when all I do is plan for an aquarium for a week.
Thanks for all the insight everyone! I'm going to draw up some schematic plumbing plans and see how they work.