I have a 4000 gallon pond that has a skimmer and a biofalls. I've been wanting a bog area for marginal plants & wildlife for a long time now. We even had a guy come out but when he said it would cost $9000 to do what we wanted we basically cracked up laughing. I mean come on if I had that I would have had the pond professional built in the first place! In any event he keyed me on to bog gravel filters. I've been reading and I totally understand how to build one, the depth, the size of the gravel, the surface area and how it works.

We want to redo our waterfall, we were planning on moving it back and making a small stream that would feed into the pond. Well now that we are going to do that might as well add the bog filter! So we want the stream to feed it but the water needs to run down the stream and then under the bog for upflow through the gravel and plant roots.

I saw the thing at the link below which is a preformed bog filter that does that but I don't want to use a preformed thing.

Is there a way to diy this? We spent a good amount of money on getting a quality pump, skimmer and biofalls and because of that we really want to reuse them.

Thanks!

I like to fed the bog with the pump output, which sounds liek what you'll have, rather than putting the pump in the bog.
For this the bog water level has to be above the pond, liner overlaps making sure there's a gap between the 2 liners to stop wicking.

If you want the bog just for plants, which they're great, you can have any shape. If you want the bog to may be help clear water you want as long a bog as possible. Basically a below surface stream. You can wind a narrow bog back on itself so the result is any shape and the top can be covered in gravel so you don't see the bends. A narrow bog can also wrap around the pond several time, go out around the yard, anything you want.

I am finishing up the bog on my new 450 gallon pond. (I lack space, so little ponds get tucked in little spaces.) I have the plumbing almost finished, but I am fussing over it a lot more than with my barrel or trickle filters. Fixing a mistake is a lot harder when you have to move a few hundred pounds of gravel to get to it.

Rather than have the stream feed into the bog, I would suggest you build the bog away from the pond and let the bog water spill into the stream. This will look very natural, like your stream is spring-fed.

After a lot of reading I realized that I was overlooking an obvious and easy solution. Based on where I'm putting the bog area I can just use a valve to divert the water and run part to the waterfall and part to the bog. Duh! lol.

I don't have a lot of room to move the bog away from the pond, the 'stream' would of been just a few feet on each side at the max. This way though, it will be able to spill right into the side of the pond giving me places for oxygenated water to run into the pond.