That all makes sense, but I do get stuck in the details.
- I don't quite get the part about providing a valve/hole to break the siphon. If this is in the inlet piping, won't water being pumped in also leak out of this?
- Do I need to make a clearance between the bottom and the start of the gravel? Some designs include this (e.g. using aquablox), seemingly to allow sediment to collect at the bottom. I know some use large rocks at the bottom for this purpose but I just imagine the pea gravel filling in the gaps.
- Do I need to split and run multiple PVC pipes into a manifold along the bottom? Some designs seem to do this, but it looks like it would make it much more complex, especially if it ever needs cleaning out.
- 2" is quite a bit bigger than the outlet on the pump I'm trying to use. Will this matter?
, and if not, I wonder how it's recommended to step the size up to connect? I'll need to run soft tubing up to the start of the PVC piping. (Just found the kinds of fittings needed to attach to PVC, I think that answers that question, thank you!
- Is a cleanout valve recommended? Also not quite sure how these work.
Since I want to make it in a plastic container that's dense enough to hold the weight of the gravel + water, that takes away the worries of trying to build a box and source liner at least!
Given where I am going to position this trial bog, I'll probably need to use a pipe to return. This looks like it just needs a bulkhead fitting, larger gague of PVC than going in (to avoid overflowing), and needs to be positioned at the top of the water level - so I think I'm good for that last bit.
okies, let me help clarify;
1. yes, water WiLL come out but barely; you're talking about a hole 1/4" AND this hole + pipe is OVER your bog, so no water loss/leakage. It's the poor man's solution to adding a tee and valve to this same pipe (from your pump)
2. you have choices; it's been done both ways with varying degrees of benefit. Aquablox give you a volume/space where water can slow down and any debris can accumlate apart from your gravel. Using large rocks instead (which is what I did) gives you similiar but without the largeness of space. That is, my large rock layer slows the water down but has large openings for upward travel. Aquablox are expensive, large round 8" boulders are not. MOST use 2" pvc for their manifole, I used 4" corrugated drain pipe/tile. Both have slits cut 1/3 the way through the manifold. With aquablox, you typically also use a snorkel for cleanout purposes. In my case, I used a DIY snorkel (can you see I'm on the cheap side when I can be???). Function is exactly the same here.
I have some bog construction pics in my showcase; year 2019
3. no, you can do one line. Sort of depends on your bog shape/layout. For instance, in MY bog, it's 3' wide. Again, I use 4" pipe, NOT 2" pvc. I used (2) leads right down the middle and each is 4". Some do branches etc but it's not necessary. More even water distribution can be beneficial but it's MY belief the water will find the easiest path up anyhow, so once out of your manifold, it'll flow sideways and find those channels eventually. See, over time, crud will stick to the bottom of the pea gravel layer and water will be diverted until it decays enough to allow flow again. The water finds a way, trust me.
4. yes, there are pvc adaptors; you're good.
5. okay, this is one very important detail IF you want a cleanout; when you dig your bog (or even make one out of wood), you have to make one point the 'low' point. When cleaning out a bog, you FORCE water (a lot of volume a sustained pressure) down into the TOP of your bog. The water flows backwards and down, clearing the pathways. ALL this 'bad' water now has to go somewhere, hence the cleanout. Putting this cleanout at the low point guarantees all this crud+water ends up there. INTO this cleanout, you will have a secondary pump. As you force water down through your bog top, you' also pump the dirty water out the cleanout. So, two pumps. IF you're going to dig this, another important pont is to shape your bog walls like a 'V'; this too forces the bad water down to your low point.
What you'll find is IF your bog water level rises faster than it can get out (of your pipe), you'll be needing to put in more pipes. General rule of thumb is outlet size diam = twice the inlet size. So if 2" in from pump, 4" out, or have (2) 2" outlet pipes. What I did with my basement mini bog is use a mason plastic mortar box, 3'x2'x8". I cut and heat shaped a weir on one side that is about an inch lower than the top fo the mortar box. So, water rises up through the gravel and before it reaches the top, it pours out the weir blade. I have my mini bog overhanging my winter pool and it just flows out and over the edge like a sheet waterfall. I can attach a pic...brb
I'd not bother with cleanout, snorkel, aquablox or large bouders unless you are doing something large. Pot type bog filters don't need such as they're easier to clean/mess with.
I have my pump going to the black garbage can where a bunch of bioballs are; they fill up, overflow into an outlet pipe (the white pvc) and then down into the mini bog to it's manifold. I used to have a prefilter in the garbage can but nixed the idea for more biofiltering. I just set it up a week ago, so plants are still getting going. Second pic shows the weir blade waterfall I cut and heat shaped.
Okay, that wasn't so bad, now was it?
