IS IT POSSIBLE TO "OVER BOG?"

[Mmathis]

Awkward title......

If I'm remembering, ideally you want your bog filter to be equivalent to about 30% of your pond's surface area.

What happens if you go over that?

Say, you have a MAIN bog, then have secondary, mini-bogs? I'm thinking of a renovation which would include re-doing the part of the pond that interfaces with the turtle habitat. I am now referring to that area as the "turtle bogs," as there are plants in there and the water does recirculate.

My renovation idea would include a more effective bog system where the turtles are. It probably wouldn't be quite enough to serve as the MAIN filtration. But then if I have the MAIN bog filter, too, wondering if this would be over-kill......

Can't decide where to go with this. Will work on getting some pics up.

 

[addy1]

To me it would just be more filtration, to me the more the better. Mine is big, I most likely will never have to worry about the fish load in my pond.

 

[dieselplower]

I would not imagine there would be a problem for the pond with too many bogs. The problems I would see are that it is creating more lines, pumps, connections, etc that could leak, making the leak harder to find. Also it may be hard to grow plants in the pond if that is a desire. If you can make it leak proof, go for it.

 

[Mmathis]

I would not imagine there would be a problem for the pond with too many bogs. The problems I would see are that it is creating more lines, pumps, connections, etc that could leak, making the leak harder to find. Also it may be hard to grow plants in the pond if that is a desire. If you can make it leak proof, go for it.

I agree, but in this case the set-up is already there. It's just a matter of re-doing the turtle-bog itself -- it's already plumbed.

 

[Waterbug]

I'm not aware of anyone ever doing any kind of testing on any bog. As far as I can tell it's all opinion, so I think it's just as valid to use that same kind of logic for size. One opinion would be as good as another.

The only data I've seen is from wastewater treatment plants that send partly treated thru treatment wetlands, sometimes ponds, but long canals seem to work better. Especially in a canal type setup waste removal efficiency drops as the water proceeds thru the system. At some point there is no benefit to making a system larger. Pond type systems have the same type of deal, larger and larger doesn't mean better and better, just costlier and costlier.

Arcata has some links to data.

In a backyard pond bog a larger structure would allow for more crap to accumulate before the bog was clogged. That's good if your goal is to increase the time until clean out. That's bad if you're concerned about the build of waste, toxic gases, reduced O2, increased DOC levels. Depends on your goals. I don't think most bog owners care in the least about these issues. Some even think these issue don't exist at all. Using that type of logic the size of the bog wouldn't matter at all, you just have to believe it's the optimal size.

 

[Mmathis]

I'm not aware of anyone ever doing any kind of testing on any bog. As far as I can tell it's all opinion, so I think it's just as valid to use that same kind of logic for size. One opinion would be as good as another.

The only data I've seen is from wastewater treatment plants that send partly treated thru treatment wetlands, sometimes ponds, but long canals seem to work better. Especially in a canal type setup waste removal efficiency drops as the water proceeds thru the system. At some point there is no benefit to making a system larger. Pond type systems have the same type of deal, larger and larger doesn't mean better and better, just costlier and costlier.

Arcata has some links to data.

In a backyard pond bog a larger structure would allow for more crap to accumulate before the bog was clogged. That's good if your goal is to increase the time until clean out. That's bad if you're concerned about the build of waste, toxic gases, reduced O2, increased DOC levels. Depends on your goals. I don't think most bog owners care in the least about these issues. Some even think these issue don't exist at all. Using that type of logic the size of the bog wouldn't matter at all, you just have to believe it's the optimal size.

WB, I guess my main concern isn't so much for efficiency or convenience, as it is that I wonder if there would be enough "stuff" to sustain all the plants. I have visions of bog and pond plants struggling to extract an adequate amt. of nutrients in order for them to survive & thrive.

 

[addy1]

TM I don't have a ton of fish, around 200 or so, no koi, just gf. Don't feed a lot. My bog is large stuffed full of plants, I do have plants in the big pond, stream ponds, preform ponds, shubbie tank, all thrive. I did not fertilize the lilies or lotus this year , they have bloomed and grown great all summer, the bog plants have shown no deprivation. It does deprive the string algae and green water of nutrients, never have those issues in the big pond. The small slow moving ponds suffer from some string, they get fed unfiltered water from the big pond. Even in those ponds I never have the green water issues.

So no real data, just observation, very pleased with how my system works. In all my years of bog filtering ponds, never had an issue with the bog clogging or getting yucky horrible. Again just observation, no hard core data, just eye balling it and water tests.

I bet you would have enough poo to sustain the plants. (you could always throw in fertilizer! lol)

 

[Mmathis]

TM I don't have a ton of fish, around 200 or so, no koi, just gf. Don't feed a lot. My bog is large stuffed full of plants, I do have plants in the big pond, stream ponds, preform ponds, shubbie tank, all thrive. I did not fertilize the lilies or lotus this year , they have bloomed and grown great all summer, the bog plants have shown no deprivation. It does deprive the string algae and green water of nutrients, never have those issues in the big pond. The small slow moving ponds suffer from some string, they get fed unfiltered water from the big pond. Even in those ponds I never have the green water issues.

So no real data, just observation, very pleased with how my system works. In all my years of bog filtering ponds, never had an issue with the bog clogging or getting yucky horrible. Again just observation, no hard core data, just eye balling it and water tests.

I bet you would have enough poo to sustain the plants. (you could always throw in fertilizer! lol)

Sounds like what I want to hear! Thanks!

 

[fishin4cars]

TM, I don't think you can have to large a bog for the plants to be short come of nutrients. Like WB kind of started. The biggest issue is when it needs maintained, the chore of cleaning can be quite over whelming. and at some point that is something to consider. As you saw my bog is set up similar to Addy's. I made a huge mistake. I planted it with mint, and it has taken over. This fall I am planning on stripping and starting the bog over. The mint is causing several voids and is clogging areas so water is backing up and leaking in a couple of places, the mint is choking out some nice plants and it keeps spreading and growing and I'm sure there are now areas that could be producing the build of up waste, toxic gases, reduced O2, increased DOC levels as Waterbug mentioned. Something I considered but didn't prepare well enough ahead in advance. Several smaller bogs may quite easily be a better situation than one large one. That way a total strip wouldn't be necessary. I also think by drilling holes in my bottom pipe instead of cutting slots I'm catching more debris in the pipe and reducing the amount of sludge that actually reaches the plants. The gravel stays fairly clean where there is good water flow, but is clogging where there is heavy rotting. That really has me wondering what is going on down deep in the gravel bed near the pipes. Are there voids that are causing some of these issues that WB mentioned. I have to say, there is a good chance the answer may be yes.

 

[HTH]

I second what WB has said in post #5. It is important.

 

[Mmathis]

Guys, no need to worry about my willingness to clean [flush] my bogs once they're up & running! I plan to have a flush-out system, and I'm sure I'll be be doing that to the extreme As it is now, my SKIPPY, which is supposed to NEVER need to be back-flushed [yeah, right!] gets a purge at least once a week -- and it lets off some pretty gross crud, too. I can't imagine NOT doing regular flushes!

No, again, the main point of my original question was more related to AVAILABILITY OF NUTRIENTS for all plants, bog and pond.

Larkin, thanks for the heads-up! NO mint in my bogs! But then, I have various mint varieties planted in the 2 turtle habitats [one that smells like chocolate -- heavenly!], so I can still have my mint-fix.

 

[fishin4cars]

Maggie, that is one good point about having the mint, all my turtles love it too. Dixie gained almost a full pound this summer. Dozer .5 lbs. That puts Dixie up to just shy of three pounds, Far cry from the 100# plus she should get to when full grown.

 

[Waterbug]

WB, I guess my main concern isn't so much for efficiency or convenience, as it is that I wonder if there would be enough "stuff" to sustain all the plants. I have visions of bog and pond plants struggling to extract an adequate amt. of nutrients in order for them to survive & thrive.

I see. That would have a lot to do with the specific plant type, how it's planted and the age of the bog. For example when I planted Canna rhizome in bog gravel I had a hard time with them. The rhizome rotted or dried out and those that rooted didn't do very well. I assume a nutrient problem. Those grown in pots filled with soil and buried in the bog gravel did well reliably. Those in pots and also fertilized did really well reliably. They also had to be divided every year or they'd be half the size.

This seemed to be true for all the soil type plants I tried, Cattail, rushes, pickerel, sedges, etc.

Many pond keepers focus on nutrients in water and seem to think this is a rich environment. But pond water, even with what a fish keeper would consider high ammonia or nitrates, is a relatively low nutrient environment. Plants really have to be specialized to survive and do well living on nutrients just in pond water. When you look at the root system of something like a water hyacinth I think it drives the point home. Compared to the green above water part the root system is massive compared to pond plants adapted to growing in soil like Canna, Cattail, Rushes, etc.

Plants with runners, like mint, water clover, Horsetail, etc., seem to do OK in the gravel because they're pretty good at sending runners to find pockets of compost in the gravel. They don't seem to do that great in just water, even a little bit of soil seems to be a big help. And planting in wet soil they do really well. Adding fertilizer to these never seemed to be a big help, but kind of hard to tell since these aren't tall or flower. But I think the age of the bog was important too. In a new bog the runner plants didn't always do well. In a 2+ year old bog they did much better as the compost built up in the gravel.

So bottom line I don't think the size of the bog would matter hardly at all as far as the number of plants and nutrients go. Plants not adapted to the low nutrient environment of pond water would do poorly whether 1 or 20 plants. It's much more a function of nutrient concentration rather than total amount of nutrients. Plants like single cell algae are adapted to low concentration. The very persistent and widely believed concept that plants adapted to soil pull lots of nutrients out of water has never been true. To do well they need soil which is much higher in nutrient concentration, whether in a pot or just a 2+ year old bog that has very rich compost (fish poo, uneaten fish food, decomposing plants like algae). And to do really well many of these need additional fertilizer unless the bog is like 5-10 years old and really packed with compost.

A bog is basically an underwater compost pile. Very rich nutrient environment. So the more food you feed the fish the quicker the bog would become a better compost pile. And also the depth of the bog would effect this. A 12" deep bog that was more surface area than say a 3' deep bog would support soil based plants much faster. The process could of course be sped up by adding organic matter to the bog gravel.

 

[Mmathis]

Well stated, WB!

 

[crsublette]

This year I planted all types of Mint along my stream. They were anchored in the big river rocks with their roots fully submerged in the stream. They grew quite well. Obviously, due to the river rock, this restricted their root growth and so this controlled their size. Still, they grew to make a nice solid growth of green down the banks of my stream. A few even bloomed. It worked out quite well. Not to say this would be true for all plants, but I have had good luck with the various Mint plants.