Ponds with viewing windows

[poconojoe]

I have a planter box bog on my hot tub pond ( 300 gallon pond). About 2 feet long about 10 inches wide. Full of pea gravel some kitty litter and plants. It helps keep the water really clear and healthy.

Any size helps.

Exactly!

 

[Worrywart]

Exactly!

That’s sounds about for our size of pond, thank you !

 

[Worrywart]

Concerning a bog filter....in your case your bog would be at a much smaller scale than in addy's showcase. There are many members here that have built a scaled down versions out of a long rectangular trough or planter.

From what you have there already, I assume someone is handy with woodworking. I suggest building a rectangular trough across the whole width of your pond ( or aquarium, if you call it that). Mount it toward the back, sitting on top of the structure of the pond for support.

The trough gets waterproofed by laying an EPDM liner inside it. A PVC pipe is layed in the bottom creating a manifold. Slits are cut 1/3 through the PVC every inch or so. This manifold is completely covered with at least 12" of smooth pea gravel or smooth river stone. Make sure your trough walls are 4"-5" taller than the top of the gravel for expansion or just to play it safe. Plants are grown directly in the gravel, no pots. They aid in the filtration process by thriving on the excess nutrients.

Water is pumped from the pond through the manifold pipe, rises up through the gravel and flows back to the pond via a spillway or waterfall on the side of your bog trough.

Any questions....just ask...

To give you an idea of the basics, here is a link to my recent bog build. Don't get discouraged, mine is a much larger scale than you would need.
https://www.gardenpondforum.com/threads/my-add-on-bog-build.26848/

Thank you for such a helpful reply . I feel quite encouraged now to give this a go. At present the pipes from the filter go into the pond, if it’s ok il send you a picture tomorrow as I’m not sure how that will work.
thanks very much, much appreciated .

 

[poconojoe]

Thank you for such a helpful reply . I feel quite encouraged now to give this a go. At present the pipes from the filter go into the pond, if it’s ok il send you a picture tomorrow as I’m not sure how that will work.
thanks very much, much appreciated .

My pump is a submersible one. I have a flex PVC coming out of the pump going over the wall between the pond and bog. The flex PVC then switches over to standard ridgid PVC which the manifold is made of.

In your scaled down version, you can use a bulkhead fitting to enter your trough bog toward the bottom of one of it's walls. Inexpensive bulkhead fittings allow you a watertight transition from the pump hose to the manifold pipe inside the trough bog.

 

[Worrywart]

Hi all,
my husband is starting to make the trough and so the arguments begin! It will be The width of the pond which is just over 6 feet and I know it has to be about 16 inches deep ? But how wide - is 9” wide enough ? As it backs onto a fence I dont really want it any wider as it will encroach too far over the pond .
plus with the pump does it have to enter the trough at the base so the water goes up through the shingle via the manifold or can it go over the top of the trough to avoid cutting holes in the trough and liner ?? Sorry if I’m appearing dim
checked the existing filter tonight and it’s really clean , all the sponges and brushes have never looked so clean yet the pond has never looked so grim.
lastly do we need a UV with the bog filter or would you run the bog filter alongside the existing filter and UV.
thank you , sorry for all the questions, I really want to do this attached some pics for you to see.

 

[poconojoe]

As far as bog size goes... if you have a large fish load, it's generally thought that the bog surface area should be about 30% of the surface of the pond.

If these parameters are met, you should be able to get away without a UV light and filtering with only the bog. If the bog is smaller, you may have to keep your existing filter running along with the bog. The best scenario is filtering strictly with the bog. That way it's less maintanance. You will never need to rinse any filters out. Just sit back and enjoy clear water.

You said the bog will be 16" deep. That's great because you want 12" of pea gravel (or small smooth river rock) to cover your manifold while having 4" for wiggle room above the gravel.

You certainly can run the hose or pipe over the wall to feed the manifold. You don't need to make a hole in the trough. That's what I did and I concealed it as best as I could by piling rocks on and around it. You can still see my hose coming out of the pond a bit, but it's not bad. My flex PVC hose is black, so it's not too noticeable.

So, let's figure the surface area of your pond and bog...

Your planning on your bog being 6 feet by 9 inches. 6 feet is 72", so 72"x9"=648 square inches. Your planned bog is 648 square inches.

You said your pond is 6 feet wide, but don't think you mentioned the measurement from front to back. Post that number and we'll see if you can get away with only the bog as your filter.

 

[Worrywart]

The dimensions of the pond are

1940mm long x 1025mm wide x 790mm tall or 6ft 4 inches x 3 feet 4 inches x 2ft 6 inches . The trough will be the length of the pond, the height of the trough will be 16 inches that’s fine, but the width is what’s causing angst, I want it as narrow as possible to avoid encroaching into the pond too much.
we don’t really mind keeping the existing filter but I’ve read that causes the bog plants to die off as they aren’t having the nutrients ?. not sure if that’s true ‍ Obviously though be better to just use the bog I guess.

thank you so so much for this , really grateful

 

[poconojoe]

If my calculations are correct, your bog trough would need to be 12" front to back instead of your planned 9" to be fully efficient. At 9", that gives you 648 square inches of surface area in your bog.
30% of your pond's surface area is 912 inches, so you're little short, but not too bad.

Keep in mind that the 30% figure is not set in stone. Every pond is different. There are many factors that come into play. Amount of fish. How large they are. What variety of fish. How much you feed them.

I say build it the size of your liking, run the bog along with the filter for about 3 weeks, then try turning off your filter and see how the bog does all alone for a week or two. Maybe it will be just fine.

 

[GBBUDD]

Looks like the water is pretty murkey there are some ways to make the water clearer

 

[GBBUDD]

The bog does not need to be rectangular it can be any shape look at addy hers is 27 feet long by only 4 feet wide. mine is 14 x 9 nothing says it can't be in the shape of an L or what ever it just may create some challenges.

 

[Worrywart]

If my calculations are correct, your bog trough would need to be 12" front to back instead of your planned 9" to be fully efficient. At 9", that gives you 648 square inches of surface area in your bog.
30% of your pond's surface area is 912 inches, so you're little short, but not too bad.

Keep in mind that the 30% figure is not set in stone. Every pond is different. There are many factors that come into play. Amount of fish. How large they are. What variety of fish. How much you feed them.

I say build it the size of your liking, run the bog along with the filter for about 3 weeks, then try turning off your filter and see how the bog does all alone for a week or two. Maybe it will be just fine.

Brilliant thank you so much , I will keep you posted

 

[Worrywart]

Looks like the water is pretty murkey there are some ways to make the water clearer

yes that’s the reason for my post really. Keeping the water clear is a real challenge so we are going to try the bog filter approach and hope it improves things

 

[GBBUDD]

If you do it right and large enough it will the other thing to consider is a canopy lesson the amount of sun

 

[GBBUDD]

at the bottom of this post in almost too small a print there is a blue link below my post here its hard to see it can show what a bog can do

 

[Worrywart]

If you do it right and large enough it will the other thing to consider is a canopy lesson the amount of sun

Yes that’s a very valid point too. I live in UK so it’s not hot and sunny generally but we have had some hot weather lately, thank you il will consider that