GPH for Bog Filter..?

[crsublette]

And all would exhibit higher efficiency with a low flow rate.

Of course... except how low do backyard hobby water garden ponds really gotta go... Our pond's bog is not filtering effluent from a wastewater treatment facility nor is our bog's being supplied with a high nutrient concentration experienced in hydroponics....

Quite interesting the points you and @Mucky_Waters have raised.. To be honest, this conversation has, at least, persuaded me to give this issue more thought..

 

[Mucky_Waters]

Of course... except how low do backyard hobby water garden ponds really gotta go... Our pond's bog is not filtering effluent from a wastewater treatment facility nor is our bog's being supplied with a high nutrient concentration experienced in hydroponics....

Quite interesting the points you and @Mucky_Waters have raised.. To be honest, this conversation has, at least, persuaded me to give this issue more thought..

I'd love to jump back in this conversation, but I'm limited for time right now. The only thing I'll bring up again is the point that you can't really compare one pass wetland systems to recirculating systems since one only gets one shot at it very long HRT are absolutely necessary to achieve optimum nutrient absorption, this is not necessary with a recirculating system that gets many chances to absorb those missed nutrients. And that when it comes to nutrient uptake in a planted bog, gauging the health and growth rate of your plants should be a pretty good way to determine if you have achieved optimum HRT.

 

[Nepen]

wow this is such a good read. Thanks everyone who contribute!

My bog is about 1/4 size of my pond but the area where plants are thriving are smaller due to the fact that I didnt design my bog so well and water will clog up if I plant 100% of the bog. So i can only plant half of the bog and the rest for water to run through. I now plants a few more plants in the stream where water flow slower so that should also help with nutrient uptake. I'll see what else I can do to maximize my space without blocking the water flow.

From the discussion i think my pumps may be too high for my bog. But I have 2 pumps so I might try to shut one down to see if i get a better result.

 

[crsublette]

I'd love to jump back in this conversation, but I'm limited for time right now. The only thing I'll bring up again is the point that you can't really compare one pass wetland systems to recirculating systems since one only gets one shot at it very long HRT are absolutely necessary to achieve optimum nutrient absorption, this is not necessary with a recirculating system that gets many chances to absorb those missed nutrients.

I think what you are getting at is called a "pollutant equilibrium"...

Depending on how fast the pollutants are being reproduced and how fast the pollutants are removed per pass... this will ultimately determine optimum flow rate through the bog so to prevent a large accumulation of nutrients still remaining in the pond...

The previously talked about "one pass" wetlands are receiving insanely high levels of polluted water... so takes more time (lower flow rates) to clean... really that simple...

 

[crsublette]

And that when it comes to nutrient uptake in a planted bog, gauging the health and growth rate of your plants should be a pretty good way to determine if you have achieved optimum HRT.

...so I might try to shut one down to see if i get a better result.

Exactly...

...I highly doubt everyone's pond's water is so polluted that their bogs need to be 5 times the size of their pond (or basically convert the pond's floor to emulate a lake floor, along with all of the extra plant maintenance this requires) so to achieve a very low flow rate, a 24 hour retention time, and still have the pond water recirculate at least 1 time per hour...

...so... test and observe... and... if ya need more plants or lower/increase water flow or a bigger bog, then keep that as an option in the plans and what possibly could be done.

 

[crsublette]

Also, when the "vegetation filter" is outside of the pond, I found much easier, less detrimental to the fish, when I become lazy or too busy to doing proper plant trimming maintenance, etc.

So, I am a bigger fan of external "vegetation filters" versus this idea of a "planted lake bottom filter" in the pond.

 

[Meyer Jordan]

"planted lake bottom filter"

Please elaborate. Have never heard of this concept.

 

[crsublette]

Please elaborate. Have never heard of this concept.

...referring to @MitchM 's experiment... at least that is what seemed like to me what he was trying to achieve... experimenting in the aquariums before doing it in a pond...

https://www.gardenpondforum.com/threads/soil-substrate-pond.17305/

 

[Meyer Jordan]

...referring to @MitchM 's experiment... at least that is what seemed like to me what he was trying to achieve... experimenting in the aquariums before doing it in a pond...

https://www.gardenpondforum.com/threads/soil-substrate-pond.17305/

Ok. What MitchM's experiment replicated were some of the features and processes related to the bottom of any earthen pond, constructed or natural. It is known as the Benthos and is, in fact, the primary source of biofiltration within any natural body of water. It would certainly work in a Garden pond, but water clarity would greatly suffer especially if the pond housed Koi.

 

[Nepen]

Exactly...

...I highly doubt everyone's pond's water is so polluted that their bogs need to be 5 times the size of their pond (or basically convert the pond's floor to emulate a lake floor, along with all of the extra plant maintenance this requires) so to achieve a very low flow rate, a 24 hour retention time, and still have the pond water recirculate at least 1 time per hour...

...so... test and observe... and... if ya need more plants or lower/increase water flow or a bigger bog, then keep that as an option in the plans and what possibly could be done.

yep. I think for me i can use how much/often string algae i get (or how fast they grow) as a factor to see if my bog needs more or less water flow/more plants .
Water quality is great.. just the string algae!!!

 

[Lisak1]

This is a great thread - lots to"ponder".

 

[crsublette]

Ok. What MitchM's experiment replicated were some of the features and processes related to the bottom of any earthen pond, constructed or natural. It is known as the Benthos and is, in fact, the primary source of biofiltration within any natural body of water.

Then that's what I am talking about when referring to "planted lake bottom" since @MitchM 's experiment is what I had in mind when writing it... "Benthos" is a much better description..

@Meyer Jordan , I appreciate the elaboration and clarification!

...but water clarity would greatly suffer especially if the pond housed Koi.

...and that is one reason why I would rather implement it as a bordered addition inside the pond (like the pictures you have previously shown https://www.gardenpondforum.com/thr...at-horse-only-figuratively.19413/#post-308628) or bordered island or an external container...

It would certainly work in a Garden pond...

No doubts from me... I have read plenty of testimonials, from folk whom rarely vacuum/net their pond bottom, that a type of unintentional "benthos" layer eventually forms, and seems to work well enough for them.... at least most of them...

I have no reason to doubt that it would not work...

 

[crsublette]

yep. I think for me i can use how much/often string algae i get (or how fast they grow) as a factor to see if my bog needs more or less water flow/more plants .
Water quality is great.. just the string algae!!!

@Nepen , Definitely worth trying...

...but don't be disappointed if it doesn't make a difference...

Bogs or little wetland enclaves only capture what is in the water column, not what has sunk to the floor... so they are only one part of the solution...


Wish I had a better camera... I need to get a better camera to describe how my pond goes through these transitions. My cellphone is old and the camera sucks. grr.

April and May much of my pond's floor and stream floor got real mucky... I normally do a quite small, spotty vacuum job (takes me 10 minutes) once a month in my pond, but did not do it in April and May.... The muck was mostly a combination of live algae, dead algae, decaying leaves, etc...

When June came along, water heated up, worm and snail population exploded, all this muck has nearly disappeared. I have all sorts of red worms and snails in my stream and pond floor... I guess this would be trying to imitate a "Benthos" layer as @Meyer Jordan talked about...

I just started to do a "small spotty" vacuum job earlier this week (takes me 10 minutes at most)... due to what has remained is basically soil particles, blown in from the crazy winds here, that just accumulated in spots.

I barely had to vacuum much.... The worms and snails basically cleaned my stream so clean that it was like I just power washed it and the same with my pond's floor... just had some small dirt piles accumulating on the stream's edges and spots on the pond floor..

I was especially surprised by this since most of Fall last year my pond was empty due to me doing a major remodel to it (basically removed a ton load of rock out of the pond), added some tangential water jets to improve water circulation, a bigger water pump, and now working on improving my fountains... wasn't until the end of Fall did I fill it with water again.

Only place a have a tiny bit of string algae now is where the muck remains in a rock pile next to 3 of my basalt rock fountains. Likely I am just going to keep the string algae there since it is contained at the moment and looks pretty neat where its at...

 

[Nepen]

@Nepen , Definitely worth trying...

...but don't be disappointed if it doesn't make a difference...

Bogs or little wetland enclaves only capture what is in the water column, not what has sunk to the floor... so they are only one part of the solution...

I wont be disappointed...too badly hahaha, no it'll be fine either way. I havnt start it yet, some how i think they muck i got is way more than the amount of fish i have (same amount in my old pond, but way a lot less muck there, about the same size fish too, goldfish only, they dont grow too big) and I do not feed them. so I dont know where're the muck came from.. probably from my gazillion snails

 

[crsublette]

probably from my gazillion snails

you should see my skimmer basket... since I increased the water circulation, my skimmer works better... Now, there must be about 50 snails floating in my skimmer basket.