DIY lookdown tank with DIY sump

[jtf74]

My tiny yellow tang has grown quickly in the year and a half I’ve had it in my 55 gallon and was starting to get a little too aggressive with my 4” maroon. It never used the scalpel but would threaten it back into his nem harem. I had planned to upgrade when the yellow got bigger and had bought a larger tank but decided to change course. Ultimately, I want a large, at least 4’x4’, lagoon tank but that can’t happen till after the remodel and after I’ve saved a few thousand dollars just for the tank.

I stumbled across some youtube videos where people had used livestock tanks, and rubber pond liners to create indoor marine ponds. I noticed immediately that the larger fish in these systems weren’t swimming back and forth along the front glass from one end to the other, as I’d seen on so many very large long narrow glass aquariums, but rather in more random circular patterns. I decided this would be a good inexpensive way to upgrade for my tang and also have greater capacity to start building up my livestock list for an eventual lagoon. It also means no glass cleaning, no moving of heavy tanks as it could be built in place. Now that its up and running, I really like the view as it feels more natural and interesting to see the fish from more of a three dimensional perspective rather than the one flat side you see in a glass aquarium.

The tank is 3.5'x5.5' and 280 gallon plus 30 gallon sump/refugium. Total cost was about $200 for lumber, $125 for the 45 mil liner, $50 for the underlayment, and $100 for a DIY wet/dry sump/refugium combo made from food grade dog food containers. I’m running a 1200 gph Jebao in the tank and a 500 gph pump for water to the wet/dry so another $150 there. Has also been lined on the bottom and sides with 1.5" rigid insulation.

Sump on left bottom now has bubble magnus skimmer and refugium on the right has a 3-4" sand bed with chaeto and mangroves (adding a couple more inches plus chaeto) and is gravity fed so no pumps to kill copepods.

Current fish are:

Yellow tang

Bicolor angel

Purple firefish

Staghorn damsel

Maroon clown- 1.5”

Bumblebee goby

Will be moving 9 RBTA’s , a large 4” plus maroon and royal gramma ( 8 years old, hoping it will live to see the big tank) from the 55 after the lookdown 300 is established enough for the nems and hoping the clowns will bond. Plan to add one of the nine nems to one corner for the small maroon first and then box in the larger one with the other 8 nems with ceiling grid to see how they get along after the first nem is thriving.

Would like to add:

Flame angel

Blue hippo tang

More staghorn damsels

Some anthias

Midas blenny

Couple royal grammas

Corals:

Xenia

Kenya tree

Green star polyps

Zoas

Mushrooms

Ricordea

Would like to add:

More zoas

Blue polyps

 

[Reeferstin]

This is awesome!

 

[jtf74]

This is awesome!

Thanks. The fish certainly think so, and I love having all the equipment in a back room, as it is much more quite. Have also rigged a spicket on the Jebao pump so water can be easily pumped out for water changes by plugging the return end and opening the spigot .

 

[gabrieltackitt]

Super cool! Would love to see more as you get it going! Definitely following along!

 

[AlexG]

This is a great looking tank. I have been looking into building some pond liner tanks in the future. I think the low cost and high water volume makes them a great solution for moving large tanks as you can setup a temp pond liner tank to hold livestock while the main display is moved.

 

[jtf74]

This is a great looking tank. I have been looking into building some pond liner tanks in the future. I think the low cost and high water volume makes them a great solution for moving large tanks as you can setup a temp pond liner tank to hold livestock while the main display is moved.

It allows me to start obtaining the livestock, skimmer, equipment now a little at a time and space to grow out fish and coral so when I finally do go to a large acrylic lagoon I won't have to turn around and spend another big chunk of cash on livestock to fill it. I will also know that all my fish are compatible together already so no trying to catch a fish from the final display setup. I'm still working on the outside and top of the plybox, and will update when done. For me it made sense because I will be opening up my outer walls of my basement replacing windows and siding in the summer and the rigid insulation will help keep the temp in check during cool nights and the sturdy box will be easier to protect during construction than glass.

 

[jtf74]

This tank now. Had a big screw up and lost half my nems. This was taken a month ago so they are recooping and better but look pretty bad in this video.