Build! 4o Gallon Reef Tank

The siren call of the sea, the peaceful reef environment.  It was bound to happen to me eventually.  The call to build a saltwater reef aquarium.

Don’t get me wrong, I love my big planted tank.  But, I thought maybe it was time for a new challenge, and I just happened to have the perfect empty spot in my living room for a new aquarium.

As my new reef setup sits waiting for the addition of corals and wildlife, I thought this would be a good opportunity to document what I’ve done so far to get it up and running.

Ideally, this will be a brief overview of each part of the build and I’ll write some more indepth how-to and review articles in the future covering more of the details of individual parts of the build.

I’ll include a parts and component list at the end with links.  Let’s start at the beginning.

Tank and Stand

The first part of any aquarium build will be.. the actual aquarium.  For this build I snatched a 40 gallon breeder tank during a Petco $1/gallon sale for… $40

I went with the Breeder tank because of its design.  Breeders sacrifice height for more floor space.  A 40B aquarium is 36 inches wide by 18 inches long and only 17 inches deep (tall.)  I always regretted the 60 gallon aquarium because it’s basically a 55 gallon but a little taller and very narrow.

Having more floor space is almost more preferable to having more height.  It provides more area for the fish to really use and gives you far more aquascaping options.


After an overnight leak test (hey, you don’t want to find that out AFTER you set everything up). I sprayed the back glass a nice deep blue.

I opted against drilling the tank for bulkheads.  I’m pretty sure the Aqueon aquariums only have tempered glass on the bottom.  I didn’t want to find out the hard way, plus I didn’t trust my drilling skills.  Even though an external overflow is more expensive, one broken tank would have negated any cost savings.

For lighting, I splurged and grabbed the 36-48″ Current USA Orbit Marine LED fixture.  It’s the single most expensive thing in this build, but worth it!

Next up was the stand.  If you do any searching for a stand that can hold a 40 gallon b fish tank, you’ll probably see that there’s a 36″x18″ metal garage shelving unit out there that fits the 40b tank so well it’s like it was custom made.

That’s the option I used and then clad it later (more on that in a bit). I found the shelf on Amazon for a little less than what my local big box hardware places were charging.

I opted to build the shelf as a 3-foot tall shelf rather than using the whole 6 foot tall assembly.  You can do either, but remember, you have to slide the tank in from above to fit it into the shelf.  The tank sits on top of the metal rails on the shelf.

40b aquarium garage shelf

Sump and Refugium

While not technically necessary for a successful saltwater aquarium, I decided I would go with the full package.  As an added bonus I had a leftover 29 gallon aquarium taking up space in my storage shed.

As a side note, if you’re buying a new tank for your sump/refugium, do not use a 29 gallon tank, it’s too tall.  Use a 20 gallon, or even get another 40 gallon.

I then had my local Lowe’s store cut up a few pieces of glass to size (it was well under 20 bucks for all the glass I needed). I used three pieces on the left for a bubble trap (two pieces mounted high, the middle piece low).  The fourth piece went on the left to create a compartment for the return pump and the second side of the refugium in the middle.


It turned out pretty ugly to be honest, but most people don’t stare at their sump for hours on end.

I also threw in a spare hidden LED from my big tank for the antec lights and bought an inexpensive LED light which I mounted across the refugium section to help the algae grow.

The small light is on a timer to give the refugium 12 hours of daylight overnight in an off cycle from the display tank.


Now I have the two tanks, it’s just a matter of connecting them.

As I mentioned earlier, I opted to not drill my tank for bulkheads.  This means I have to use an external overflow.  I heard great things about the CPR CS50 overflow.  It’s a little more expensive than others, but it’s built well and it’s not a component you want to fail.

Speaking of which, the CPR is often mentioned as optionally needing an aqualifter pump.  That is so not optional.  You need either an aqualifter or a strong powerhead with a venturi.  The reason is that in the event of a power outage, you will lose the siphon in the overflow.  The auqalifter removes the air from the siphon chamber starting the siphon automatically.

One final think to know about the CPR CS50 overflow, it’s bulkhead is listed as a 3/4 inch outlet.  Which is true, but it’s a 3/4 inch PVC, if you’re using flex hose, you can find an adapter online.  Or you can do what I did and get creative at the plumbing department at the home depot.


I did take the opportunity to add a ball valve inline with the overflow.

To return water from the sump I went with a Rio pump of a similar GPH rating as the overflow. The Rio came with a ball valve already to control flow.  I mounted the pump using the included hanger.

By mounting the pump high up in the tank, that meant it wouldn’t end up draining the whole sump into the display tank and flooding the place should the overflow fail.  It’s important to allow enough extra room in both the sump and display tanks to compensate for failure of one of the components.

Rather than getting fancy with hard pipe, I opted to use 3/4″ inner diamater flexable hose.  It’s maybe not as optimal as using rigid PVC, but it’s a lot easier to work with.

It turns out that even though the Rio had a higher GPH rating than the CPR overflow, it could not return water fast enough, causing the CS50 to gurgle.  I carefully adjusted the valve coming off the overflow to slow the flow until the pump and overflow were going at the same rate.

Balancing the two took a little work.  If I closed off too much flow, the display tank would overfill until the pump started to run dry. Eventually I reached flow nirvana and the levels in both tanks stayed the same.

Assorted Other Stuff

The basic infrastructure covers the build, but I wanted to point out a few other things that are part of the build.

I used an existing 200 watt heater I had from a previous tank.  In addition, I coupled an air-powered protein skimmer with a Whisper pump I also already had.

For powerheads, I started out with inexpensive SunSun powerheads as I’m such a big fan of their filters.  But, I also used a plug in wave generator which alternates which pumps get power.  It turns out the SunSun wavemakers don’t work too well when you turn the power off and on.  I ended up buying a pair of much more expensive Hydor Koralia wavemakers which work beautifully.

As for the hardscape in the display tank, I went with 50 lbs of Florida dry rock from at less than $2 per pound it’s a great deal.  I seeded the sump with some live rubble I picked up on eBay.

Finally, I didn’t want my nice new reef aquarium to look like it was sitting around on some industrial shelving.  So I hit Home Depot for some beadboard paneling and trim and knocked together a series of panels that attach to the metal shelving via magnets.  I’m pleased with the results.

cladded tank

Parts List

Here’s a link to most of the stuff I bought for this project.  Some of these links may be affiliate links (If you buy something, I get a small percentage).

Tank and stand




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