Bog building, also called upflow filter, eco filter, wetland filter

[tbendl]

Wow, I just spent an hour trying to find a place to buy pea gravel in bulk... I had absolutely no idea that this was like searching for lost treasure. As a tip, for anyone else who doesn't have a quarry or rock shop nearby, ( I don't even know if a rock shop exists but if it did, I'm sure it'd be full of ponders)...anyway as a tip, concrete companies use pea gravel. That is where my rainbow ended and I found my pot of pea gravel. Is there any issue with using it that anyone knows of?

 

[addy1]

lol I bought all of my pea gravel from a concrete company, other rocks from a rock quarry.
no issues, we did not clean it, we are on a well and it was a dry summer.

 

[tbendl]

Addy1, I really like the rushes you have planted but you had indicated that they root deeper than other plants, how much deeper? And can I put marginals in my Bog as well? I'd really like some color and think I might be ok with not having to winter them since I'm so far south

 

[addy1]

The roots go down about a foot the others around 1-5 inches. Put plants in test them out, some will make it some won't. I have marginals planted they do fine.

 

[CountryEscape]

OK, here you go. Pretty sure this is VERY close to how Addy did hers, or I would not have offered. I just have these pics close at hand, have had many people want to know just how the pipes go together. When I was building, pics are what made it all make sense. Let me know if you have any questions, or Addy will be right here to answer them!
I drilled holes in the pipes, but I think now I should have made the holes larger, or maybe used slits (with a cut off saw) instead. Be sure to turn the pipe so the holes or slits are facing the liner.

Here are the water lines the way I put them together. The black ribbed line is flexible sump pump tubing. It has worked extremely well for me, lasts through winter very well, no cracked or broken lines at all. Then fittings to go from the sump pump to the white PVC. When you lay it out and fit everything together, glue them as your final step.

View of the pipes laid out in the empty bog, before pea gravel is added. If you have a curve, use curve connectors in the PVC parts. Clean out ends have caps on them, not glued, just tightly pushed in place. You can use screw on caps if you prefer, which is what I have in my other bog. Need to be able to open them up to flush the lines if necessary.

 

[tbendl]

Ok that helps a lot. I had found a few pictures when you did your build on another thread but I am glad I can use flexible hose to get from the pond to the bog. Now as I understand it, I would have a pump on the bottom of the pond with the tubing going to the bog area but do I need to put something in between the pump and the bog to allow drainage for doing a backwash? I have also noticed people put some type of a large particle catch in between to grab any big stuff flowing from the pump to the bog, do I need to consider that? I don't have fish and I would put my pump in some type of enclosure to keep leaves from being sucked it and also put the pump slightly off the ground.

 

[addy1]

We used a chop saw, cut 1/3 or so of the way through the pipe, opening pointed down, also put an extra piece of liner between the pipe and the real liner. I have a leaf basket between the intake and the bog, (external pump)

 

[tbendl]

So since I won't be using an external pump there really is no need for that provided I keep the leaves off the bottom of the pond? And yes, I did read how you laid out your liner and pipes with the chop saw cuts down so no gravel gets in.... Now to build it....

 

[CountryEscape]

Tbendl, I have my 4200 gph pump on top of a milk crate. I almost NEVER have to worry about stuff getting caught on the intake "cage". I have not added anything extra than what came with the pump. I think the fact the leaves will settle to the bottom, not much goes through the pump. My pump is set up to take larger stuff that some, so keep that in mind. But, to me, key is to keep the pump off the bottom of the pond. That black flexible sump pump tubing you see goes directly to my pump. The only thing you should maybe consider is a one-way valve, or whatever they are called. If your electricity goes off, the water will drain to the pump, and since that is lower than the bog, you may pretty much empty your bog. If you put a one-way in-line between the pump and the inlet to the bog, that will keep that from happening. I have my other bog running from the skimmer pump, and have a one-way on that line, too. Learned that after I had to shut off pumps for moving things around, and noticed the water in the bogs was draining down lower than level of the pond.
Is that what you are referring to as "backwash", not letting the water wash back into the pond? For flushing the bog pipe/lines, (sometimes called backwashing ...) I open the clean out pipes and run the water right out the top. I do that a couple of times a year, or if I notice the flow out of the bog decreasing.

 

[tbendl]

Great point about getting a one-way in-line for my pump. I am not planning on running the pump 24/7 so this is a great tip. Thanks CountryEscape.
Addy1, I have gone back over the pictures and am looking for a close up of the waterfall area from bog to pond. I have my bog somewhat formed, (a double lower ring of concrete blocks topped with a single ring and about a 20" gap for the water to flow) but my issue is the liner is pretty bunched up from trying to fit the curves from the pond to the top of the bog. (I'll take some pictures tonight) but I'm trying to figure out if I just put a heavy rock on top of the scrunched up liner in that 20" gap for the waterfall feature? I read about making sure to angle the rock downward a bit but I am a little worried about all the folds in the liner. I also considered using metal of some kind and putting thin flagstone on top of it. That would allow me to have more length extending into the pond. And then how do I keep all the gravel from flowing over the rock? Like I said, I am having a hard time visualizing how this whole thing fits together. I looked at rebelangel_3733's pond since her bog build is really similiar to mine but the last video of hers, the water looks like it's flowing under the rock and not over.
AND... lastly. Calculating pump size so I get a good flow over the waterfall.... Do I do the same as I would for a filter and calculate it based on pumping the total volume of the pond in 2 hours? Or is there a different way to calculate?
So yeah, I got questions...

 

[Mmathis]

Bringing up good points & questions, and I haven't checked Addy's thread in a while.

1. What's the best back-flow-preventer valve to use? My bog will be totally above pond level, so if there is a power problem, I don't need the entire contents of the bog flowing back into the pond!
2. This one is regarding the slits or holes -- since there is going to be a pressure difference between the water as it's closer to the source vs that at the end of a pipe, do you need to make the slits/holes closer together or farther apart at any point?
   

 

[tbendl]

I have the same issue with my bog being higher than my pond. As far as the slits go, I'm pretty sure Addy1 placed the slits further apart at the beginning so that the entire bog would be "watered".
"I don't think it would matter, we used two 25 feet long 2 inch pipes. We made less slits closer to the input of the water, more slits at the end of the pipes, now years later I don't think it would matter how you make your slits. Ours are from 10 inches apart to about 6 inches apart, no real measuring going on. Just hacked a pipe with a circular saw." <--- I found what Addy1 said back on page 16.

 

[addy1]

Some say turn over every 1/2 hour some say every two hours, Mine is about 1.5 hours more or less.

I put a large piece (3 foot wide) flat rock, for my bog water fall. Under the rock (I had a smooth liner under the rock) I gooped it up with pl roofing goop. That made the water go over the rock not under. You could put some sort of compound between the rock and the scrunched up liner to seal the area, that way the water will go over the rock not under.

The pea gravel does not flow out, I had it level with the rock, it does not move, after settling some it is around 1/4 inch or so below the rock, don't worry about it wandering out of the bog.

The angle of the rock, with it slightly pointed down the water flows over the end in a nice waterfall. If it is angled up it tends to flow over and then under the rock, i.e follows the shape of the rock. Being angled down it will not make the pea gravel flow out of the bog.

 

[addy1]

lol you all are typing while I am slowly typing with my sore hands.To much rental reconstruction..........

My bog is above the pond by around 8 inches or so, the piping go into the bog from the pump. The piping is higher than the bog where it comes out of the bog, enters at the bottom of the bog, when the pump shuts off it does not back flow into the pond. Must have something right lol. A little air intake will stop it from back flowing if the pump stops, it breaks the suction. I did that with a house tank and a home make filter.

 

[tbendl]

Roofing goo. Got it. I should be able to smooth the tip of the liner where the rock will go but the front side is all bunched up. I have to go rock shopping and see what I can find that will jut out far enough to reach the pond. Have you seen anyone use sheet metal covered with slate maybe? I was wondering if I would get a little more distance there.
And addy1, I think I read someone drilled a small hole in the pipe at the top of the bog that breaks the suction in the event the pump is shut down so it doesn't reverse suction all the water out of the bog. I'm going to try that since I won't be running any type of in line filter.
Thanks for the clarity about the rock, I was racking my brain trying to figure out how to get the water up and over the rock, not down and around it.