Need help with Simple Bog Filter

[AndyZoner]

Hey Everyone,

I've read through addy's bog building 101 and have a basic idea of the bog I want to build - Simple, pea gravel, PVC, lots of plants. I'm hoping you awesome folks can point out any glaring mistakes and help me work through the construction parts of this.

My pond is 8'x10' and about 700-800 gallons (first pic). So I need 24 square feet of bog to get that magic 30%. I've got the space, but I'm not sure how to utilize it. The area to the right of the pond/waterfall box is 3' wide and 11' long (second pic). It has a 6" slope from the front to the back (third pic). It also has a 6" drop on the right (fourth pic).

The pump is in the skimmer box on the left of the pond and the outlet from the pump is plumbed into the bottom of the waterfall box.

I want to make a simple/inexpensive, dug out and lined, up-flow through gravel, PVC bog filter. I'd like to incorporate the waterfall box somehow, but I can take it out if need be.

Right now, I've got this list for how I "think" I can put this filter together:

1. Level the bog area.

2. Construct cinder block wall around the perimeter of the bog - 18" high. Leave a 16"x3" space open on the pond side of the bog for a waterfall.

4. Install underlayment and liner. Liner on pond side should go over the cinder block wall and down to the pond liner. There's about a 3" space between the water level and the top of the pond liner (fifth pic). Do I bring the bog liner under the rocks anchoring the pond liner (keeping the bog liner over the pond liner) and then seal the two liners together? How is the bog liner usually handled when it's separate from the pond liner?

5. Piping.... Should I cap off the inlet in the waterfall box and run new flexible piping inside the pond from the pump in the skimmer box to the bog? Or do I dig up the buried piping and bring it over the edge of the bog back by the bush?

7. Put in 2" PVC piping just like addy's bog - I feel good about this part. 1/4" slits at a 45 degree angle down and extra liner under the pipes to protect the full liner and a pipe that comes out the top of the bog for unclogging.

8. Fill 12" deep with 3/8" pea gravel and bring in rocks to make the outside look more natural. Put in lots of bog plants.

Is there a way to incorporate the waterfall box? I wouldn't mind having 2 waterfalls. My husband suggested I split the water flow between the bog and the waterfall box, but I'm worried that the water will follow the path of least resistance via the waterfall box.

I've attached a picture of the bog area with some simple measurements and here's a video of the area via Google Drive: https://drive.google.com/file/d/1hf7Z2utCKu5r5C4K6GoFFvJNkn_F29Oj/view?usp=sharing

 

[addy1]

How neat! You are bog building! I don't even have a clean out pipe, but I also do not draw the water from the bottom of the pond.

 

[Tula]

We built a small bog a year and a half ago. Ours is very basic and the liner just drops into the pond...it's grown algae over it, so not very noticeable. We still have our main water fall.

 

[poconojoe]

Your basic description is similar to mine, but I used rocks instead of blocks. I have plenty of rock on this mountain.

My bog is based on addy's build. She has inspired many of us.

Have you seen my bog add-on thread? It might help you in a couple of ways...

My add-on bog build

I finally did it! I joined the bog club! The bog is approximately 14 feet by 5 feet and about 12 inches deep. I know my 1600+ gallon pond has been overpopulated due to my fish reproductive rates! Last year the water never cleared up to my liking. I figured my two pressure filters and my...

www.gardenpondforum.com

 

[AndyZoner]

We built a small bog a year and a half ago. Ours is very basic and the liner just drops into the pond...it's grown algae over it, so not very noticeable. We still have our main water fall.

So there's no worry of water wicking up? It'd be really nice just to let it drop into the pond. I could even cover it with my planting pockets...

 

[AndyZoner]

Your basic description is similar to mine, but I used rocks instead of blocks. I have plenty of rock on this mountain.

My bog is based on addy's build. She has inspired many of us.

Have you seen my bog add-on thread? It might help you in a couple of ways...

My add-on bog build

I finally did it! I joined the bog club! The bog is approximately 14 feet by 5 feet and about 12 inches deep. I know my 1600+ gallon pond has been overpopulated due to my fish reproductive rates! Last year the water never cleared up to my liking. I figured my two pressure filters and my...

www.gardenpondforum.com

Would you believe I've had your thread bookmarked for the last few days? The more I look at it, the more I like it.

 

[poconojoe]

When I overlapped my bog liner over the pond liner, I didn't use any sealant.

My existing pond liner wraps over the wall into the bog and the bog liner lays over that and extends about two feet down and into the (pond) water.

I have a shallow shelf at water level where my first row of big stones lay on the new liner. These stones are half submerged. Then I kept stacking stones on top of that, eventually covering the liner wrapped wall.

I don't know if that all makes sense...

 

[AndyZoner]

When I overlapped my bog liner over the pond liner, I didn't use any sealant.

My existing pond liner wraps over the wall into the bog and the bog liner lays over that and extends about two feet down and into the (pond) water.

I have a shallow shelf at water level where my first row of big stones lay on the new liner. These stones are half submerged. Then I kept stacking stones on top of that, eventually covering the liner wrapped wall.

I don't know if that all makes sense...

It makes total sense.

 

[poconojoe]

Would you believe I've had your thread bookmarked for the last few days? The more I look at it, the more I like it.

I think the basic concept is very similar to what you have in mind.
We think alike

 

[poconojoe]

I don't have a skimmer or a waterfall weir.

I pull my water from the other side of the pond with a 3600 gph submersible pump. It hangs about a foot off the bottom, supported by a thin rope.

I have black flex PVC running along the bottom of the pond, up over the wall into the bog. I covered most of it with stones as it goes over the wall.
No plumbing is outside the pond. If any of the plumbing springs a leak, no water will escape.

 

[poconojoe]

If you do split the water between the waterfall box and the bog, you can add a valve to each so you can fine tune them individually.

 

[AndyZoner]

If you do split the water between the waterfall box and the bog, you can add a valve to each so you can fine tune them individually.

So clever - I never thought of this - I could put the piping in the bottom of the waterfall box. I love it!

 

[poconojoe]

So clever - I never thought of this - I could put the piping in the bottom of the waterfall box. I love it!

Easy peasy.
PVC pipes and fittings are inexpensive and easy to work with.

 

[Tula]

So there's no worry of water wicking up? It'd be really nice just to let it drop into the pond. I could even cover it with my planting pockets...

We have a lot of extra liner so we have stacked rocks on the side of the bog and the liner goes up and under the stacked rocks. We originally wanted a more finished water return to the pond, but couldn't figure out a way to do it.

 

[addy1]

So there's no worry of water wicking up? It'd be really nice just to let it drop into the pond. I could even cover it with my planting pockets...

If it is high enough it won't wick. Or make a air gap, I had to put a air gap in our loop pond, minimal drop from one to the next, used a piece of hardware cloth between the liner the pond edge, no wicking.