Completed Barrels
The picture above shows the
first day of operation of completed
half-barrels in their temporary location.
More plants and fish came later.
Barrel Banner
After looking at other filterless container ponds, I decided that for a little effort, an under-gravel filter could be added to eliminate the scum and support a higher fish load with clearer water. The contents of this page are unique in that I describe in detail how I made a couple of half-barrel ponds with under-gravel filters.

This is a brand new page and there's other excellent half-barrel pond pages on the Web. If you want to create a small container pond, check out the links at the bottom of this page.

We were looking for a quick distraction from our never-ending backyard construction. I decided to build a couple half-barrel ponds for our backyard. A large Koi pond was in our plans, but there was at least a year of other construction to complete before the Koi pond was started. Not only would two half-barrel ponds would pacify us in the interim but they'd make a nice permanent addition to our backyard. Further, I wasn't planning on having many plants in the Koi pond, but the barrels could support heavy water plant life.

I bought two half-whiskey-barrels from Home Depot for $14 each (I found some without holes in the bottom). The truck smelled like a brewery once the barrels were loaded. Although Jeff's Half-Barrel Pond Page and Van Ness Water Gardens pages suggested the use of a liner, I hated to buy a $25 45-mil EPDM liner for my $13 barrel, but after scraping the barrels' interiors, rinsing, and filling with water and sitting for a week, the drained barrels still smelled like 80 proof.

OK, so a liner it is... The bottom of the barrels were about 20 inches in diameter and the sides were 15 inches high. A 4.5' square liner would do it. I had a roll of heavy 4-mil poly plastic and although I knew that the Internet pond community would rise up against me, I though I'd try it. What a great idea that was -- both barrels leaked.

So now I've been beaten into submission -- I'll buy a real liner. The local Armstrong Nursery wanted $29 for a 5' x 5' whiskey barrel liner. My local Koi dealer (Andrew's Koi International 714-778-8888) was out of stock on the 5' x 5' 45-mil EPDM whiskey barrel liners (which would've been $20) but I could buy 5' wide, 9' long 45-mil EPDM for $25 -- enough to line both barrels -- what a deal!

Under-gravel filter cut-away
Here is a cut-away sketch of the under-gravel filter. The water and gravel are not shown for clarity.

Shooter with filter grate Although it's not necessary, I chose to build simple under-gravel filters to provide clearer water and to support more fish. The construction of the filter is simple and cheap. I bought one panel of the "Eggcrate" white plastic fluorescent lighting diffuser at Home Depot for just under $9. It's 3/8 inch thick with holes just over 1/2 inch square. One panel was more than enough to make both filters. I used a saber saw to cut two disks the same diameter as the inside bottom of the barrels -- about 20 inches in diameter. Here to the left, web-star Shooter models with a cut-out filter grate.
Eggcrate lighting diffuser
I bought two 79-cent 4"-diameter PVC end caps to serve as flanges and used some 3/4 inch schedule 40 PVC sprinkler pipe that I had laying around. The trick with 3/4 inch PVC pipe is that the outside diameter is a hair over 1 inch. Cutting the eggcrate lighting diffuser to open up four of the 1/2 inch square cells allowed the pipe to fit through the eggcrate grating. I filed the four "nubbs" that remained so the 3/4 inch PVC pipe could easily fit through. I put the hole in the grating a little off center, but anywhere at least 3" from the edges is fine.

I cut 11-inch lengths of sprinkler pipe and drilled one-inch diameter holes in the end of the 4" diameter PVC end caps to accept the pipe. I then notched the end of each of the pipes to allow water to flow in from sides. I drilled some 9/32 inch diameter holes in the side of the pipe for standard 1/8 inch I.D. aquarium tubing, just over an inch from the end. I also drilled a hole in the side of the 4" cap, and a pattern of holes in the end of the cap to allow water flow.

Shooter with filter pump tube I glued the sprinkler pipe to the 4-inch caps with Christy's PVC glue, allowing the notched end to protrude about 1/2 inch. The aquarium hose was fed through the two holes to a small air stone inside the pipe. Shooter and bottom view of filter tube

Shooter with completed filter
Here is handsome Shooter with his completed under-gravel filter

To prevent the filter gravel from falling through the relatively large 1/2 inch squares, I cut some fiberglass screen door material about 1 inch larger radius than the eggcrate lighting diffuser. I then cut a one-inch hole to line up with the hole in the eggcrate diffuser, and made one-inch cuts every 4-6 inches around the circumference of the screen to allow the screen to seal where it meets the inside of the barrel.

I found a temporary home for my half-barrels and placed them on three concrete blocks. The back barrel was placed on three leveled 6" X 8" X 16" blocks (bargain at 60 cents each). The front barrel was placed a little lower on three 6" X 16" concrete caps.

The liners were then placed in the bottom of each barrel and a couple inches of water was added to hold the liners in place. The eggcrate lighting diffuser was placed on about 20 rocks around the bottom of the barrel (I had a huge pile of 3/4" aggregate), and the screen was placed on the eggcrate diffuser. The PVC pipe/endcap assembly with the airstone was inserted into the 1" hole, and a few inches of pea gravel (from my other pile) was placed onto the screen and into the "cupped" portion of the 4" diameter PVC end cap.
Shooter with water filter
Instead of adding a chlorine remover, I used a single-element under-sink drinking water filter that I'd plumbed to fit a garden hose to fill the barrels. The manufacturer stated that the filter will remove 97% of the chlorine when operated at low 1 gallon/minute flow rate. While the barrels were filling, I pleated the liners to conform with the interior of the barrels.

Both air hoses were connected to a Whisper Pulsar Three dual air pump which I bought for $14. The nice thing about a dual diaphragm pump is that you won't need valves to equalize air flow or have to constantly tweak it as the water levels change.

If you want to play Mr. Science Guy and investigate air lift pumps, turn on the pump and watch the top of the 3/4" pipe as the water rises. When the water level is a few inches below the top of the pipe, water will gurgle out.

Water Hyacinth
Home Grown Water Hyacinth
To hold down the liner, I cut some 1/8" thick by 1.25" wide redwood 6.5 feet long and screwed it to the very top inside lip of the barrel (well above water level) using stainless steel screws. The liner was held captive between the barrel and the redwood. I hope that you have better luck with the wood strips. Even though I soaked them in water and pre-bent them, they cracked during installation. Oh well, just adds character. A utility knife was used to trim off the excess liner to the top of the redwood.

I bought some water hyacinth and water lettuce which you can find at most pond shops to float around in the barrel, as well as a few taller accent water plants in plastic pots I made a couple plant shelves with the scrap eggcrate light diffuser panels from the Home Depot. I cut crescent shaped sections from the panels about 5" wide to serve as a shelf and then cut out the grid as done previously to create a ~1" square for each leg. Later we bought a water lilly.

I was amazed to find that Christy's PVC glue was able to bond PVC pipe to the lighting panel material. I measured the required height of the stand (from the top of the gravel to the bottom of the pots when their top edge was 1/8" under water). I then cut three legs from 3/4" PVC sprinkler pipe to this length. If you don't file the "nubs" of the 1" square cutouts, the outside diameter of the 3/4" pipe fits snugly and can be glued in place. Eggcrate lighting diffuser

Shooter with plant stand In the picture to the left, Shooter's crooked head is hiding the center leg of the plant shelf. I purchased the shelf material from The Home Depot and placed it on the gravel against the back of the barrel. I placed the potted plants on top which have so far stayed in place but they'll probably fall over in heavy winds -- Maybe I'll make little plant seat belts...
After a couple days of operation, I blew $4 on some bacteria/ enzyme junk to assist in establishing the gravel biofilter. I'm not convinced that bacteria-in-a-bottle does much. I initially added just two Mosquito fish and two Goldfish to each barrel. I was really itchin' to add at least one Koi to one of the barrels but Jeffrey Cook's page warns against it cuz they devour the plants. My local Koi dealer (Andrew's Koi International) agreed so they lost a sale. I figured each barrel holds about 20 gallons water so maybe the filter and plants will easily support 6 to 10 fish. Every week or two, I'd added a couple goldfish until I had six 3 - 4 inch fish in each barrel. After a month, I realized that the plants were growing too fast and I pulled some out, broke down and bought a two-inch Koi. He's now four-inch and the plants didn't seem to be doing bad, so I bought two more 4 - 6 inch Koi. The plants are doing fine, and the Koi tend to be the party of the barrels. Goldfish

Every week I replace about 20 percent of the water. I monitor the ammonia and nitrites -- They're always low and the water is always crystal clear, and never any scum. To clean the under-gravel filter, I use a siphon gravel vacuum to clean the pea gravel. I replace the lost water with water run through my filter. I'm considering building a water-powered vacuum like the kind used in cleaning Jacuzzi spas.

The air stone in the filter will clog every year or so but it's easy to replace. Just push back the pea gravel from the 4" PVC cap, pull the cap and pipe assembly, replace the air stone.

Stanley London Solid Brass Medium Pocket Compass $20
Stanley London Solid Brass Medium Pocket Compass $20

Jeff's Half-Barrel Pond Page
Murphy's Fish in a Barrel
Doc Johnson's Koi Care
Anjon Pond Liners

visitors to my Cyber-Backyard.

Stanley London Brass Sextants
Stanley London Brass Sextants and Nautical Collectibles

Shooter's Yorkie Fun Page
Visit Shooter's Yorkie Fun Page

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Eric Newman * Copyright © 1997 - 2017 * Revised 6/12/2017