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

[addy1]

I open that valve and let the pump push out sludge buildup, when that becomes necessary.

I have a two inch drain pipe on my bog. Have opened it a few times, nothing but clean water comes out. I do not have a void.

The back areas of the bog have become like wet lands, roots , dirt have made very wet land.

 

[GBBUDD]

That will work to a degree but The force of the water will take a single path and not so much flushing the whole system. The one difference i did with my bog was to have the centirped pitched toward the snorkel and i mean with a good 1/2" per foot I leveled off the area with large boulder with big spaces to any debris could fall back to the centiped and slide down to the snorkel where it can be pumped out

 

[DanielleB]

There's lots of marketing around the centipede unit, and it does serve several purposes, but the primary one, in my opinion, is that it is below the blocks and sloped to the snorkel so that junk actually makes it somewhere that you can remove it. Most milk crates have a lot of solid area around the top. Most of mine had about 3". So, your void will eventually fill up and you'll never get what settles in those bottom 3 inches out. Maybe not the end of the world (don't know...), but a permanently smaller void.

Tell us more about your discharge plan. How are you discharging? Is your bog totally above ground so that your can drain it from the bottom with some sort of valve you access outside the liner?

How does this group feel about using Infiltrators as a replacement for the centipede?

 

[GBBUDD]

@DanielleB what are you calling an infiltrator.
After having a 24 inch hdrpe culvert pipe and getting zero sediment. When I redid my bog 8' x 20' I opted for the aquascapes centipede as it is low profile making the bog need less of a retaining wall. It paid for it's self in that regard.

 

[combatwombat]

How does this group feel about using Infiltrators as a replacement for the centipede?

Are you talking about septic leach pipe? Kinda looks like half of a culvert pipe with slots in it? If so, that's a great product to sub for a centipede. I think most of us use culvert just because it's easier to find.

 

[GBBUDD]

used culvert because the price was right FREE

 

[Pond skipper]

Hi all, just about to start rebuilding my waterfall and bog, originally the waterfall fed the bog but I’m going to an under gravel system this time. I’ve been doing a lot of research and I’m getting conflicting info, I understand everybody has their own opinions and that’s what I’m looking for.. other opinions. Firstly I’ve read in some places and seen videos where they insist the slots or holes in the pipe be facing down and other places they say up. Also some places say use no more than 3/8 pea gravel (which is what I have) other places seem to say you should vary the size with larger rocks at the bottom then a larger gravel in the middle and finish with the 3/8. What is everyone’s opinion on these issues? Also, I can’t seem to find a good diagram or explanation of the clean out pipe. Does it connect into the under gravel pvc at the opposite end or does it stand alone in the gravel, do you just flush clean water down it (like filling a hole) or is it better to attach a fitting that you can connect a hose to to get some pressure. And then how does the flushed out water escape the bog without going into the pond. I know, I know, probably basic questions but I’m a basic kinda guy.

 

[GBBUDD]

i don't know where your finding down flow in a wetland that is not at the bottom of the pond. I have seen recently as i only just started going on FB , BUT MY GOD have i seen some seriously painful suggestions

 

[addy1]

Mine, running 12 years now, slits down, no clean out pipe, large and deep, 2.5 feet, filled with only pea gravel.

 

[Lisak1]

I'm always interested to read people's ideas - I mean the wetland filter started with an idea and developed from there. And like any idea it went in lots of different directions. Some of those ideas succeeded - others failed. If you have the time, money, energy and will to fail and try again, then going outside of the box is always an option. If you prefer something that has stood the test of time, then you go with what has worked for others.

One of the great things on this forum is you'll find descriptions of wetland filters of all types that work. Anyone or any website that tells you that you MUST do one particular size rock or THIS EXACT METHOD or ONE KIND of product is wrong. It's a basic principle that can be achieved in a number of different ways, as you can witness in real life right here on the GPF.

 

[Tula]

My sand and gravel filter is set up with graduated size rock, finishing with granite chicken grit. I believe there is a small void in the bottom and it's cleaned by using a blower to flush the debris from the bottom and out a discharge pipe to the yard.

It has stood the test of time and is still kicking . I wonder if we'd devised something similar for our failed bog if it would have worked?

 

[Pablo]

Hi all, just about to start rebuilding my waterfall and bog, originally the waterfall fed the bog but I’m going to an under gravel system this time. I’ve been doing a lot of research and I’m getting conflicting info, I understand everybody has their own opinions and that’s what I’m looking for.. other opinions. Firstly I’ve read in some places and seen videos where they insist the slots or holes in the pipe be facing down and other places they say up. Also some places say use no more than 3/8 pea gravel (which is what I have) other places seem to say you should vary the size with larger rocks at the bottom then a larger gravel in the middle and finish with the 3/8. What is everyone’s opinion on these issues? Also, I can’t seem to find a good diagram or explanation of the clean out pipe. Does it connect into the under gravel pvc at the opposite end or does it stand alone in the gravel, do you just flush clean water down it (like filling a hole) or is it better to attach a fitting that you can connect a hose to to get some pressure. And then how does the flushed out water escape the bog without going into the pond. I know, I know, probably basic questions but I’m a basic kinda guy.

I'm getting ready to build my bog in a week or two if I can ever finish rocking in my pond, lol. I have read many threads here and watched videos. What I try to do is take a compromise approach. One thing that is clear is that there is no hard and fast rule book for bog building. It is not like anyone here or somewhere else can point to a scientific study that states categorically having slits or holes face up is demonstrably better than face down. There are too many variables with ponds to have any definitive answers, I go with the basic science behind it of water flowing through gravel which creates bacteria that plants can feed off and that helps to clear the water. If you put too many fish in the pond then no matter how you design the bog you will have problems, same thing if you do not plant enough.
I personally decided to go with the slits down, cut a third through the pipe, most people say slits rather than holes because the holes can clog easier. FYI, something that is not mentioned, cutting those slits makes a mess so be prepared to clean up a lot of PVC off the floor, it goes everywhere, also clean the pipes afterwards since the stuff gets in there also. I did my slits 3 inches apart after reading people doing 1.5 inches, 3, inches, 4 inches and 6 inches, I decided to go in the middle. Also at the end of the day is the bog really going to fail because your slit was off by an inch, no it is not.
I have three manifold pipes, I have a clean out pipe at the end of each one, again that seems to be the consensus. Some have a bottom clean out pipe. I will have a screw on cap on the clean out pipe (you can get the screw on fitting and screw on cap at plumbing supply houses online, they are a unique fitting so you will probably not see it at Home Depot. Some people do not have a clean out pipe and they do fine. A lot of people say not much comes out of the pipes when they flush them out, it seems like you do not have to do it much. When it comes time to do it, you turn off the pump, take the cap off and attach a hose or pipe to direct the water out of the bog, turn the pump on and the water will shoot out, guess it does not take long.
You are ahead of the game by doing a bog, dont stress to much about the exact details and keep the basics in mind.

 

[bobchapman]

Leaking bog!
I have a bog that is 8' x 16' x 18" deep, with EPDM one-piece liner (no seams), and 18" of pea gravel filling it.
When left idle (no water being pumped through it), the water level drops to 6" below the rim of the bog. So, obviously, it's leaking. And I know at about what level the leak is happening (6" below rim). I'm removing the gravel around the periphery of the bog, hoping to find the broken spot. But how will I know if I've found it: I'm expecting a rather small tear or puncture that might be detectable by touch: is that a reasonable thought?

Also, the gravel is pretty dirty (see photo). When is it too dirty and in need of removal, washing, and re-installation?

Thanks for any help
Bob

 

[Pond skipper]

That’s a good question. I don’t think it hurts the gravel to be dirty more nutrients for the plants I would think but I’m no expert. Mine was similarly dirty and I wouldn’t have washed it yet if not for the fact that I emptied the bog to look for the leak so I washed it before I put it back. I never found the leak. Couldn’t find any holes or tears so I threw a whole new piece of liner over top of the old and filled it back in. Still leaking!!! Wtf. Anyway, good luck finding your leak, let me know if you figure out a way to find it

 

[Pablo]

Leaking bog!
I have a bog that is 8' x 16' x 18" deep, with EPDM one-piece liner (no seams), and 18" of pea gravel filling it.
When left idle (no water being pumped through it), the water level drops to 6" below the rim of the bog. So, obviously, it's leaking. And I know at about what level the leak is happening (6" below rim). I'm removing the gravel around the periphery of the bog, hoping to find the broken spot. But how will I know if I've found it: I'm expecting a rather small tear or puncture that might be detectable by touch: is that a reasonable thought?

Also, the gravel is pretty dirty (see photo). When is it too dirty and in need of removal, washing, and re-installation?

Thanks for any help
Bob

Sorry you have to go through that. I just filled my new bog with the gravel this past weekend so the thought of having to remove all that would freak me out. No expert at all, looks like you have mortar in the wall, maybe with the water pressure the liner pressed up against some sharp mortar that may not have been smoothed out. Also, how quickly does it lower the 6 inches? and how long have you had the bog? Did you have underlayment before the liner? Peace of mind you may want to just put a new liner in if you go through the trouble of digging out that much gravel. Not great options I know. I would not worry about washing the gravel since that has the good bacteria you want.