Question on plumbing from BD to settlement

[Catfishnut]

Mpagri,

Waterbug, Howard The Humble and Mucky_Waters have covered everything about your bottom drain system and water flow very well. I wanted to add a comment or two here and there, but as I read onward I found they already covered it and more.

There is one thing that I see has not been covered, however. This is based upon my impression of your title for this thread: "BD to SETTLEMENT" and you described using two 55 gal drums for settlement tanks. What I would like to know is how you have these drums fixed to perform the settling action?

You will not be able to utilize simple "stagnant water" or "still water" to precipitate out the debris because with the flow rates you are going to be working with, there will be too much water flow in such a small vessel size. Almost all of the particles will continuously remain suspended because there will always be water flow. Some particles will float naturally, regardless of the flow rate, some will be neutrally bouyant (meaning they will hang around in the middle) and only a few particles will be heavy enough to sink to the bottom.

You will have to adopt some form of a baffle system to sediment out or settle out debris and separate it from the moving water. I think that there are several methods which would work to roughly settle your debris from your water, but you will have to also apply other mechanical methods to fully get the job done.

A baffle system such as a radial flow filter + a sieve type filter might be something you may need here.

Look into these searches:

Radial Flow FIlter Paul Van der Werf:

Mr1Superb sieve filter in a barrel:

Then another thing you might like to research is a septic system design, I don't have a specific link for this, you'll just have to research it.

Like everyone who replied here previously, the problem (or the answer) is not gravity, it is the water flow or fluid dynamics. You can get the water to "dump" its load of muck if you harness the power of water properly. This isn't exactly easy to accomplish in our backyards without going to the university and becoming a fluid dynamics engineer ourselves, but we can devise a fairly dependable system based upon these principles that will perform reasonably well. We can copy some ideas and theories and notions and then experiment with them with our DIY mentalities and come up with a pretty fantastic system without a student debt or hiring an engineer.

Gordy

 

[bean6924]

Radial Flow FIlter Paul Van der Werf:

Gourdy,

Curious to hear your thoughts on this system. I'm thinking of installing two of these (30 gallon for 2500 gph from BD) in line. It seems like it "skims" water from the top. I could not tell from the video if this system is at the same water level as the fish tank or below. In either case, I wonder if something gets clogged, or waterflow is changed, would the system stop skimming?

 

[Catfishnut]

Bean,

I cannot speak to the recommended sizing of these radial flow settling systems vs the size of the pond, although small radial filters appear to be highly efficient and extremely effective at handling large systems with high bioloads. Therefore I believe that these systems can be real space savers.

These filters normally take the water from the bottom drain of the fish tank in the aquaponic system and separate the solids from the water and pass on the nutrients. Since plants cannot utilize solid nutrients, they have to absorb the nutrients which are dissolved in the water, you don't wish the solids to pass on to the grow bed and clog it up. So you filter those out here. If you are just trying to recycle the water for a back yard fish or garden pond, the solid separating action of these systems is just as worthy, albeit for a different purpose.

I think these aquaponics gurus set the fish tank just slightly above the radial fitler and the radial filter just slightly above the vegetable grow bed and then the sump tank sits below the grow bed and that is where the pump is located to route the water back to the fish tank and start the entire cycle all over again.

Now, I also cannot see how they can ever become clogged due to their design unless you leave them totally unserviced for a long, long time. There is too much open space within. I don't think that they ever actually become clogged, per se. What happens according to the other videos I have watched and the information that I have read is that the settled debris becomes invaded by anerobic bacteria and they create a slime layer and gases and then the debris at the bottom changes bouyancy and it starts to float to the top water where it becomes mingled with the effluent water which is supposed to be clean. So, basically it doesn't clog up, it just starts pumping the gunk back into the system if not purged when required. You don't want to leave it uncleaned for too long otherwise you get dirty water back in your system.

Gordy

 

[HTH]

Has anyone seen them used on a 5000 or 10000 gallon pond?. Could be that I have missed the larger ones or maybe people have not figured out how to scale them up.

 

[bean6924]

Has anyone seen them used on a 5000 or 10000 gallon pond?. Could be that I have missed the larger ones or maybe people have not figured out how to scale them up.

I emailed one of the guys that sets these systems up about scaling up. Have not heard back from him yet. It seems like they deal with less volume though. I'm wondering if this would work with a standard 55 gallon barrel. They basically claim that the "dwell time" is 1 minute or less (compared to 20 minutes for a settlement chamber)...

 

[bean6924]

Here is Paul's response to my question.

• 
  
  brian oleary 15 hours ago
  
  Hi Paul
  Rob Bob suggested I contact you. I'd like to use this system for a 1500 gallon koi pond, running a 2500 GPH pump to a 55 gallon (200 litre) radial flow filter. This will be pumping from a 3" bottom drain in the pond, and will pull fish waste and some leaf waste etc. Do you think this set up would work?
  
  ·
  
  
• 
  
  Paul Van der Werf 6 hours ago
  
  Hi Brian,
  You may want to split the flow through two 55gal filters. Try the 55 gal by itself but plan to put another one in line when plumbing.
  
  · in reply to brian oleary
  
  

 

[bean6924]

What happens according to the other videos I have watched and the information that I have read is that the settled debris becomes invaded by anerobic bacteria and they create a slime layer and gases and then the debris at the bottom changes bouyancy and it starts to float to the top water where it becomes mingled with the effluent water which is supposed to be clean.

Doesn't this happen with settlement chambers as well? Or would it be less often?

 

[HTH]

It is all about how long the sediment remains on the bottom.

How often are these guys draining off the sediment? If it is done weekly does the problem still exist.

This is only the first stage of pond filtration. If it does happen a screen could be used to prevent it from flowing into the next stage.

I would not worry about it.

 

[Catfishnut]

Yes, the growth of these unwanted anerobic bacteria causing gases to float the debris would occur in other systems as well if not purged frequently.
I think the major problem with the radial filter system is that those flotsams of goo can more readily exit the effluent port where you don't wish them
to go because there is no physical barrier to them. This would be especially unwanted if the next filter stage down stream would clog up because of this.
Certainly, if you were into the aquaponics stuff, you would not wish these goo masses to go directly into your grow bed media and clog that up.

I have been running through several ideas, including my own DIY designs, to perform this same task. When I happened on the radial filter item, I was
actually excited about it. It is so simple and it works on the concept that I was trying to apply to my designs, but my stuff was difficult to construct. These
systems are so flat out easy to build! A few scrap PVC pipes of different sizes or maybe some scrub buckets from Menards and a used 55 gallon drum and
you are done.... AND it works!

What I really like about it is that it can be smaller than a typical settling tank and yet operate with higher flow rates. That is a plus in my view.

catfishnut

 

[MasonJensen]

Considering a pond redesign: Upgrade drain to 4" with 45-degree angles, keep piping close to pond bottom, and reassess pump GPH based on future needs. Any insights on potential debris climb in raised piping?

 

[Mmathis]

@MasonJensen This is a very old thread. Why not start a new thread specific to your questions?