Thanks Gordy - I used my work program (AutoCAD).
Bog building, also called upflow filter, eco filter, wetland filter
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Good Answer catfishnut! 
looks great, now we need photos of the build.
looks great, now we need photos of the build.
OK, here is a photo of the stock tank (50 gal.) and the PVC fittings. Just imagine pipe and the 2 tees pointing up. Looking at this layout, I won't have room for slots on the sides, Maybe just 1 between the 45's. This will also make the front and back slotted pipes touch the container bump outs. Thinking now, maybe I should have gotten (4) 90's instead of the (8) 45's. This way I could cut some slots on the sides between the tee's and 90's. What are your thoughts? More slots better than the sharp bend of the 90's?
Oh, and these are all Schedule 40, I just didn't want to bury pipe that says it's not for pressure use.
Oh, and these are all Schedule 40, I just didn't want to bury pipe that says it's not for pressure use.
Falconut,
Once you have it glued together, you can proceed to cut slots into the 45 degree and Tee fittings themselves. You'll want that additional flow and it won't hurt anything in this application. The whole assembly is going to be supported by the tank bottom and held in place by the gravel so it's not going to break since it's not going to flex or twist.
You don't need to be concerned with the pressure rating of the pipe in this case, but the schedule 40 will be much more durable. If you ever do need to empty the gravel to move the tank, repair or alter something, the pipe will survive any shovel hits.
Gordy
Once you have it glued together, you can proceed to cut slots into the 45 degree and Tee fittings themselves. You'll want that additional flow and it won't hurt anything in this application. The whole assembly is going to be supported by the tank bottom and held in place by the gravel so it's not going to break since it's not going to flex or twist.
You don't need to be concerned with the pressure rating of the pipe in this case, but the schedule 40 will be much more durable. If you ever do need to empty the gravel to move the tank, repair or alter something, the pipe will survive any shovel hits.
Gordy
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Looking good agree with Gordy!
Thanks, then I can just proceed as planned. Since I'm snowed in today, I may try to start working on it. Is it spring yet? I'm so tired of winter already.
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Our house is snowed in, we aren't lol
I'm going to use a bog as my only filtering for a pond with a few goldfish. In the winter (which we are having a great plenty of in NJ), do you just let the bog freeze solid? Do the plants survive, or do you have to move them indoors for Winter? Thanks for any help.
Bob
Bob
I'll answer in regards to our bog. Last winter we allowed everything to freeze, but the bog still only had about 2" of ice. Maybe the gravel transferred heat? Maybe the ground heat kept it from freezing deeper? Not sure, but we were surprised that it didn't freeze solid. Our plants did all survive, with the exception of a chameleon plant that kind of struggled all summer. This year we're running the waterfall all winter (only the big one - turned off our stream and smaller fall). Obviously a much, much colder, snowier winter (northern IL) so we'll see what the spring brings for our bog.
Generally I would say most plants that you would grow in your bog would be adapted to freezing solid. They are marginal plants that are located near the surface and edges naturally where they would surely freeze in their native environment.
Generally I would say most plants that you would grow in your bog would be adapted to freezing solid. They are marginal plants that are located near the surface and edges naturally where they would surely freeze in their native environment.
Ah! Forgot to mention the calla lilies - the only plant that I did pull out of the bog, as they are obviously tropical and would not have survived the winter. I packed the tubers in peat moss and stashed them in the basement. We'll see if I can get them to grow again. I figure anything I can winter over is one less plant I have to buy again!
What do people find to be the best depth for a bog, and should it have several different depths? I'm considering building mine on a slant so that it is say 6" deep at one side and 12" deep on the other, so that I have a range of planting depths. Does that make sense? I'm thinking that the bog will be a semi-circle with a ten foot radius, approximately.
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Mine is deep, mainly because someone, i.e. me dug it way too deep. Most of my bog plants, minus the grasses, have roots that do not go past 6 inches or so in depth. Some stay just under surface of the gravel, i.e. less than a inch deep.
The grasses do go down further. Most of the reading I did suggested 12-18 inches in depth.
Mine freezes solid, the first winter it froze big time, all the plants come back. I have an external pump, I pull it during the winter it has no choice but to freeze. I do not drain the bog, leave it full of water. This winter I am sure it froze up pretty good, with as cold as it has been, (we are not there currently)
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Somebody else enjoying this crappy NJ winter weather. I'm setting up the same as you, looking to have my bog be my only filter. I'm using a container and keeping the depth less than 12", my container height. I posted the photo of it above. My winter plans are to just remove the pump and the majority of the visible pipes and leave the bog filled to the drain height and let it ride. I'm hoping any extra water just drains into pond, and freezing just expands upward. I won't know until next spring. The bog pipe will be open ended and pointing down.
Falconut,
I don't know how cold your winter temps are in general, but our highs can be as low as single digits sometimes and our extreme lows can get to -10 or -15 F.
A tank like the one you are using would definitely freeze if above ground and might freeze even if underground in our climate here.
I wonder if it would be a wise plan to install some sort of bottom drain so that you can allow all the water to run out when you go to winterize your pond stuff. You'd have to use some sort of screening mechanism to prevent your bog gravel from going out the drain, but a cheap PVC shower drain with a strainer would work just fine. If your bog tank is going to be set above ground, this would be real simple to install. If you are going to bury it, then you would have to design some underground plumbing to accomodate the drain valve and piping and the outlet.
I am concerned that if you are going to be shutting the system down (no flow through the bog) in winter, that the water will freeze and push out on the sides of the tank and break it as well as breaking the pipes inside the tank.
If the slits in the pipe do not extend to the bottom of the pipe, I would drill a few holes in the bottom of the pipe to ensure that the water drains completely and then use the bottom drain to ensure that the tank is completely drained too.
In a pond or a lake water freezes from the top downwards and since water is not compressible, the sheet of ice rises as the ice gets thicker. In a wide, smooth sloped walled tank, this might protect it from splitting the sides out because the pressure would be directed upwards, rather than outwards against the sides. However, this bog is not the same environment as a pond or lake as we have the gravel and rocks inside. The water is trapped in between the gravel. When the water freezes and expands it would push the gravel outwards in all directions, not just upwards. This would almost certainly split the sides of the tank and may even crush the pipes inside.
I hope you can see the concern I have here. I would either keep the water flow going all year long or ensure that it is fully drained, or prepare a design to do both.
Gordy
I don't know how cold your winter temps are in general, but our highs can be as low as single digits sometimes and our extreme lows can get to -10 or -15 F.
A tank like the one you are using would definitely freeze if above ground and might freeze even if underground in our climate here.
I wonder if it would be a wise plan to install some sort of bottom drain so that you can allow all the water to run out when you go to winterize your pond stuff. You'd have to use some sort of screening mechanism to prevent your bog gravel from going out the drain, but a cheap PVC shower drain with a strainer would work just fine. If your bog tank is going to be set above ground, this would be real simple to install. If you are going to bury it, then you would have to design some underground plumbing to accomodate the drain valve and piping and the outlet.
I am concerned that if you are going to be shutting the system down (no flow through the bog) in winter, that the water will freeze and push out on the sides of the tank and break it as well as breaking the pipes inside the tank.
If the slits in the pipe do not extend to the bottom of the pipe, I would drill a few holes in the bottom of the pipe to ensure that the water drains completely and then use the bottom drain to ensure that the tank is completely drained too.
In a pond or a lake water freezes from the top downwards and since water is not compressible, the sheet of ice rises as the ice gets thicker. In a wide, smooth sloped walled tank, this might protect it from splitting the sides out because the pressure would be directed upwards, rather than outwards against the sides. However, this bog is not the same environment as a pond or lake as we have the gravel and rocks inside. The water is trapped in between the gravel. When the water freezes and expands it would push the gravel outwards in all directions, not just upwards. This would almost certainly split the sides of the tank and may even crush the pipes inside.
I hope you can see the concern I have here. I would either keep the water flow going all year long or ensure that it is fully drained, or prepare a design to do both.
Gordy