I'm thinking about adding a bio/bog filter to the side of our pond (it will drain into pond) to increase filtration and aeration. We already have a waterfall and filter/uv thing but single celled algae is still a problem. Any thoughts? Any pictures from those who have done this?
bio/bog filter
Hi, Aggicorgi - I put a bog next to the top pond with a separate pump to circulate the water. It is 8' by 10' with a bottom of sand, gravel, and then stones up to 4" at a depth of 18". It has worked very well as a filter, although since I did it last summer, I don't have many plants growing yet. Hopefully, this year will bring growth to the miniature cattail, elephant ears, and cardinal flowers I have there. It's lined with 45 mil and drains back into the top pond. I'd say go for it! Dax
Here's a pic from the pond side -
How big is the pump you are using for the bog? My setup would be similar (near the falls), but somewhat smaller. What size is the main pond?
Try www.watergardening.com. Their magazine had a great article on Bogs as filters a few years back written by Anita Nelson. If I remember correctly, she owns a pond business with her husband and it is in Texas and the name of the business starts with the word Nelson. They might have a back issue or tell you where the Nelsons are located.
Folks in our water garden society noticed if the flow of water was too fast past their U.V. it was ineffective. You might check your flow rate.
I'd love to see pictures of your bog once you get it established.
Yes, I don't have a UV filter for the bog, and it's just a 350 gph pump so it is a slow filter, completely natural. The top pond is 10' X 6' and feeds into the stream and bottom pond. The bottom pond is what feeds the top pond's water. The falls is completely separate. Attached is a pic taken from the top pond/bog area so you can see the rest of the set-up. Considering the size, I think the natural bog filter has done a nice job. However, since I have a woodland pond set-up, I am not looking for completely clear water. - Dax
Mine has worked great so far. A simple setup.
My waterfall goes into it and then out into the pond.
8 X 10 x 18 inches deep.
Lined the bottom with Soda pop crates covered with wire mesh.
Added pea gravel on top of that.
Left the input and output ends open so water can flow under the crates.
Planted bog plants. They cover it so well that you can not see the gravel or the pond sides.
Here's a photo of my 'bog' filter from last summer. I have a biofilter in my waterfall, too. So when the pump takes the water from the pond through the skimmer box, at the other end of the pond, it is routed to the waterfall. I have a splitter valve just before the falls and I divert part of the flow through the bog filter. I use one pump for the entire pond - a bit over 4000 gallons. In chosing my pump, I just calculated the total volume of water I needed to push, including the bog, at the head height of my waterfall. At the diverter valve, the hose runs underneath the streambed and puts the water into the bog filter from the bottom of the bog. I used a large ball valve for this, and I have an access to it from above so I can increase or decrease the flow of water through the bog at any time.
The bog is 20-24 inches deep. At the bottom of the bog I used short shallow crates put in upside down, then a plastic mesh over them to keep the gravel from falling through. Then I filled the bog with pea gravel. Bascially I wanted to build a very large under-gravel filter just like you would buy for an aquarium. The water enters the bog from the back/bottom and it perks up through the gravel and spills over into the pond. Just about anything grows and flourishes in there! Any cuttings I take, I stick in the bog filter and they root quickly and thickly. The gunnera got huge last year. I'm considering moving it this year because it grew too fast!
This system has worked extremely well for my pond. I made my own biofalls filter, too, and used the savio filter ribbon for the inside. I recently cleaned it out and there was almost no detritus at all in the biofalls filter. While I have had string algae (who hasn't?) I have never had any green water at all, even when I add water to the pond directly from the hose. (I let it go into the pond with a shower head attachment, so the chlorine evaporates quickly. Because the pond is very large, I have more leeway with this than many other folks.)
Here's a photo of the diverter valve setup. I spent a lot of time in the plumbing section at Home Depot and Lowes getting pieces that would work for what I wanted to do. Because this hose is underground, I used a cheap sump pump hose. It took me awhile to find a glue that would attach this hose to the black plumbing pieces, but I finally did and they are holding just fine. I think it was a 'goop' product.
I have photos of the whole process, just about, because it was so much work I sometimes have to look back at them just to remember how crazy I was!
Playdish you did just what I wqangted to do. After the fact. LOL
Nice Job
thanks. Yes, it does sound like ours are a lot alike! Finding something that the gravel wouldn't fall through was a big pain. I didn't even think of wire mesh! I ended up getting this plastic shelf liner they sell at a local restaurant supply grocery store. They sell it on a big roll and you buy by the foot.