How to Install a Bottom Drain

[koikeepr]

Bottom drains (BD) are fantastic adds to ponds if you're hoping to keep your pond floor clean with minimal fuss and no vacuuming. Here's a step by step on how to install one. The bottom drains shown here are 3" aerated bottom drains.

Obviously, you need to have your bottom drains installed in the ground before your liner goes in like this:

http://i918.photobucket.com/albums/ad27/koikeepr/4172010smaller3.jpg

You then put concrete around each BD up to the lip so that it doesn't shift around with the weight of the water. After curing a couple of days, put your soil back over them, but leave a little well area all around each drain so that crud slips down into them.

http://i918.photobucket.com/albums/ad27/koikeepr/CIMG2647.jpg

Put your liner in and then let's cut the hole out for the drain opening. Don't be afraid to cut liner, it's really simple! Every BD will have a bottom plate and a top flange that fits on top of it. The liner obviously is sandwiched in between the two tightly with screws. Be sure to use a thin coat of P&L Roofing and Flashing Sealant (or aquarium sealant) below the liner and above the liner facing each flange.

http://i918.photobucket.com/albums/ad27/koikeepr/CIMG2674.jpg

Be sure to put a lot of P&L around the inner and outer edge of the flange ring, too. Here I'm cutting the middle piece of liner perfectly with a knife to make it the correct size:

http://i918.photobucket.com/albums/ad27/koikeepr/CIMG2680.jpg

Now we've got to put the dome and air pipe on. Here are the pieces. You can see that I inserted the tiny PVC parts that will be the "legs" for the dome to fit into the matching holes in the flange on the hole. You want to make sure that your dome sits no higher than 1/2" above the pond liner floor. Anything higher, and a small fish could easily get under it. You want to just be able to slip your fingers underneath.

http://i918.photobucket.com/albums/ad27/koikeepr/CIMG2678.jpg

Screw the air pipe into the hole inside the BD and remove the top part of it so you can slip your dome over it. Make sure to use plenty of plumbers tape to get a tight seal. It will look like this:

http://i918.photobucket.com/albums/ad27/koikeepr/CIMG2681.jpg

[koikeepr]

After you put the dome on and make sure the little legs are fit snugly into the holes on the flange, you screw the aerator part back on. Now, you're ready to attach your air disc by screwing it on. When you're done, the whole thing will look like this:

http://i918.photobucket.com/albums/ad27/koikeepr/CIMG2682.jpg

[WeWilly]

It's better to cut the liner after the top flange has been screwed down.

[koikeepr]

Yes, that's what I did--tho I didn't get a picture of that. In pic #3, you can see the flange has been screwed down and then I started cutting the hole.

[Squidhead]

I don't think I took any pics of my BD install. At that point i think I was racing against time and a little overheated and P.O.'ed. :hissyfit:

[ncwaters]

Can someone possibly share more detail on the plumbing portion of installing BD. What are the recommended pipe sizes? Does the 2nd (smaller) pipe coming from each drain have something to do with being "aerated"? Sorry. Noobie here and comtemplating a BD. Just not sure about the logistics of the whole process.

[lindalongfin]

Think there is a sticky done by Steve on another forum.

[Kntry]

The smaller pipe should be 1" and it's hooked to an air pump to supply air to the bottom drain.

There are different size bottom drains. Most people use 4". The larger pipe would go to your settling chamber or static chamber to separate out the larger trash.

When making cuts in the liner, be sure to cut ONLY circles. If you cut a straight line, the liner will continue to "tear".

Putting bottom drains is very simple once you understand how and why they work.

http://i140.photobucket.com/albums/r14/kntry/Pool%20to%20Pond%20Conversion/IMGP8534.jpg

I made my own bottom drains so they won't look like Lisa's but it's the same principle. 1" air line:
http://i140.photobucket.com/albums/r14/kntry/Pool%20to%20Pond%20Conversion/IMGP8522-1.jpg
4" water line:
http://i140.photobucket.com/albums/r14/kntry/Pool%20to%20Pond%20Conversion/IMGP8523-1.jpg

[WeWilly]

I would also level the bottom flange before pouring concrete

[Kntry]

Definitely, it needs to be leveled.

[Ponderer]

I see that Mike from Koi Acres used Medo air pumps and I'm satisfied with that unless I hear different, what do the ponders here use with their BDs?

[Kntry]

I have Hakko but don't like them and they're very expensive. I also have Dolphin. They're reasonable and work very well.

[Ponderer]

Thanks Sandy!

[koikeepr]

I had a Dolphin and found it very noisy in comparison to the Medo personally.

[Meganne]

why don't you like the hakko Sandy? mine runs well though the diaphram need replacing every other year or so.
it is pretty quiet

[Birdman]

Nothing but Medo for me.

[koikeepr]

I love the fact that you don't need to deal with replacing diaphragms and such. The Medo has been an utter workhorse and whisper quiet for me. It wasn't cheap upfront, but I expect to get many years out of it. It was definitely an investment.

[Ponderer]

Yes they are pricey but Medo for me, I like the way they're designed. Is there a thread on BDs? If not what is a good aerated bottom drain.

[Birdman]

Yes they are pricey but Medo for me, I like the way they're designed. Is there a thread on BDs? If not what is a good aerated bottom drain.

I like the Dream Ponds Koi Toilet 1. It's very well designed and made, and for 200 bucks you just can't beat it.

[Laminae]

OK. I see all about a bottom drain. However, where do I run the drain? What do I run it into? I need more info!!! I'm off to google!

[Birdman]

OK. I see all about a bottom drain. However, where do I run the drain? What do I run it into? I need more info!!! I'm off to google!

Please read the "Filtration Basics"Sticky (http://www.thepondforum.com/showthread.php?211-FILTRATION-BASICS)

[Appliance Guy]

I seperated both BD water and air lines, for independant control of each.

Prepared BD.

2181

Seperated 4" drain lines, also seperated 1" air lines (not shown)

2180

The 4" lines connect at the tee (shown with out ball valves in place, each line should have a ball valve). To the right of the pic are the 1" airlines. They will be 90'd over to the air pump, each with a ball valve for independant control.

2182

[Kntry]

The air lines should be independent of the bottom drains. Very good!

I set up my quarantine pond bottom drains like you did. It's not the best way to do it but it does work. Especially if you put valves on each so you can control the flow. One will always try to pull more than the other. The same with the air lines.

Be sure to put concrete under each drain so they don't move.

[Appliance Guy]

:winkgrin:

2184

[WeWilly]

I've had EA, Hakko, Alita, Dolphin, PondMaster and SweetWater air pumps and now Medo.
I would be Medo pumps for me now and in the future.

[koikeepr]

Medo are my favorite hands down as well.

[Appliance Guy]

I got the Medo 80 per everyones instructions. Plugged it in to make sure it works. Don't know how it performs (well according to most), but I was surprised on how quiet it is. I was fearing a loud chugging, but its only a vibrating hum sound. So far so good.