New 360 gallon aquarium

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.


Aquarium Advice Apprentice
Nov 16, 2014
Hello, I'm getting ready to go for doing a 360 gallon planted discus tank. The biggest I've had is 55 gallon tanks with canister and hob filters. From what I've read, it sounds like a sump system is the way to go. I would appreciate any advice regarding the most simple and easily maintained system. I am currently building the stand and was wondering if I should account for any bowing of the acrylic. The dimensions I'm planning to get are 96 x 24 x 36. I've always liked having mirrors on the back of the tanks I've had. Any recommendation for a builder of the acrylic tank itself would be greatly appreciated. I figured I would do a center overflow and have mirrors for backing on either side. I thought I'd put it right against the wall but wonder if I should leave 5 inches just in case I need anything hanging down the back. I have tons of ideas and questions but would love any advice I can get. I'm in rural Colorado and the local pet store doesn't do more than 180 gal. setups. I tried contacting a guy in Colorado springs to build the whole thing but haven't heard back. Thanks in advance for any advice!
Glasscages does both acrylic and glass. I think the largest acrylic they offer is 300 but I'm sure they'd be willing to make a larger tank. After all, money talks. There is another that I can't remember at the moment and I believe the largest the offered was 500g. Personally I'm not a fan of tall tanks simply because set up and maintenance is predictably a royal pita. I would figure at least 125-150g sump at a minimum.

I wouldn't worry so much about a lot of space behind the tank because once it's in place it's not gonna go anywhere. And if something falls behind it, I'd just go get a new whatever that fell back there. I'd be more inclined to worry that it's setup on a slab or you've put a lot of (money) support in the floor. A 360g and 150g winds up just over 4200 pounds and that's not including tanks/substrate/stand/pumps/etc weights.

As for the Discus, that's gonna be an extremely expensive tank to stock as I would only do adults in something that size, it would parallel the cost of just the tank. Juvies just wouldn't do a tank that size any justice and the cost to grow out in a tank that size would be utterly repulsive. Never mind the sump, pumps, plants, substrate, etc, that go hand in hand. Hopefully you've got a supplier that will cut you a good deal on a bulk purchase for stocking purposes.

Sent from my iPhone that doesn't like me. Or you.
thanks for the advice - I've seen several diy sumps - any recommendation on a pre-made one?
A big thing to remember with a sump is the drain-down that will occur during any pump/power outage. A 96W x 24D tank (height doesn't matter here) hold 10 US Gal for each inch of height. The formula is this:

(Width * Depth) / 231 = US Gallons per Inch Height

---> there are 231 cubic inches in a gallon

The overflow in the tank will keep the tank water level a certain height above the bottom level while the pumps are running (the higher the pump rate, the higher the water flowing over the overflow). When the pump stops this water will continue to flow through the overflow until the tank water level is at the bottom of the overflow slots.

Let's say at your setup's flow rate your tank level runs 1/2" high, during a power outage the tank will dump an extra 5 gallons into the sump. If your sump were a 55G tank, (2.5G / inch) the water level in the sump would rise 2 inches. Since most sumps have separate chambers and spill-overs your 'sump' area likely is going to be half or less of the overall sump tank. This means the extra 5 gallons would raise the 24" x 12" sump by 4 inches.

Just something to consider as your figuring things out. I have a much smaller freshwater sump setup for a 30G goldfish tank, the sump is only a 5G tank! Since I didn't need a skimmer or refugium, the sump tank didn't need to be nearly as big as a similar marine setup. I have a filtration section (8" x 3", 7" high) with course and medium sponges followed by 3" deep filter floss for water polishing and a bio section (also 8" x 3", 7" high) with over a quart of seachem's pond bio-matrix. This leaves a 8"D x 10"W x 8"H sump section that holds 2.75 G. My 24x12 tank is 1.25G/in, and draining about a 1/2" adds less than 0.75G to the sump, raising it's water level about 2.5".

Just thought I'd introduce ya to the math of the sumps... it's really pretty easy once you know how it works! With a tank that size I'd look into using pond oriented filtration (like the pads & biomedia) simply because there's no real difference and it's considerably cheaper buying in the bulk!
This is great stuff - thanks a million Jim. I need all the guidance I can get to make this work right with the least headaches possible.
We're building the stand and I'm wondering if I should leave a gap behind it. I assume it will depend on the configuration of the overflow and return plumbing but can someone give me a recommendation on this? I've seen some with external overflows and return pipes up the back and others with them through the bottom of the tank - which is better for this size of tank? I thought I would leave 4" behind it just in case but if there no need then I'll frame it to sit right up against the wall. Thanks!
Just FYI.. an AquaClear 110 HOB hangs over 4.5" to the rear. I'd suggest leaving 4.75" to the rear just in case you ever decide to add one down the road. I run an AC70 on the 30G goldfish and an AC110 on the 75G. They are the secondary filters on both tanks, but what can I say, I love redundancy!

Latest posts

Top Bottom