Mechanical filtration choices discussion.

[crsublette]

Generally, a turn over of 1 times per hour is the norm. Although, I think it should be higher relative to a higher fish stock density due to the additional dissolved gases released from the fish's respiration.

Shoot, a 10 to 1 ratio of gph to volume is nothing. Do some research into river flow pond designs. These ponds are designed in a matter where it truly does reflect a river and you can see the water current, that is there is a river head where the flow begins and then the river's mouth where the water is quite still for the fish to rest. Also, moving helps the fish to better digest their food, which allows the fish to consume more food to create more nitrogen for plants, which makes it for an interesting application in aquaponic gardens.

 

[Litzi1964]

When I was researching pumps and filters, numerous sources said the pump should turn over the pond volume every hour, which would be a 350 gph pump and filter. That's basically what I started with (a combined filter and pump) and it was grossly inadequate even with only 10 inches of fish. With just that filter my pond would've turned into a swamp. A 10 to 1 gph to volume ratio means the entire pond volume is turned over every 6 minutes. Mine is about 6 to 1 so the entire volume should be turned over every 10 minutes. I have about 30 inches of goldfish so I shouldn't be overstocked.

 

[crsublette]

Right now, true, you are not overstocked.

Wait 3 years and you will be unless there are improvements to the bio-filter.

Goldfish are slow growers, nothing like koi. The potential adult size of a fully grown goldfish is around 10~14 inches if fed quite well.

I am hesitant about using the term "overstocked" since it is quite relative to the volume and quality of filtration, circulation, and attention to water chemistry. However, for beginners, I would say 50 gallons per goldfish could be a heavy fish load.

 

[Litzi1964]

What I don't get is common online and library sources say
1) a pond pump should move the entire water volume every 1 to 2 hours
2) for goldfish, 10 gallons of water per inch of fish is ok

Using that theory my PMK 190 should be fine for a 350 gallon pond and 30 inches of fish. If i just ran my PMK 190 my pond would look like a swamp in a matter of hours. Granted, my pond is in the southwest corner of my yard and gets full sun, and my plants are small still.

I started with the PMK and added to it. I clean the PMK and the submersible box 3 or 4 times a week. The canister gets cleaned every month or so.

 

[crsublette]

Yep, everyone have their own general rules. It is one reason why this hobby is so dang confusing due to the contradiction of everyone's "general rules", that also includes product manufacturers as well !!! :cheerful:

In regards to frequency of filtration maintenance, this entirely depends on the construction of the filtration. As mentioned in this thread, I spend extremely little time on my filtration maintenance, a total of around 10 minutes out of the entire week, and can leave it alone for weeks without issue, but I paid through the nose for it. Good stuff, including DIY'd stuff, has a significant cost to it, but I think they are definitely worth the cost only if you can afford it.

Please, do not allow all the "stuff" in this hobby add to any personal financial nor relationship strain, because, then, I think this hobby becomes less of a tool for enjoyment, less of a tool for serenity to our self and others, and less of a tool to connect people. So, don't allow this to happen. This hobby should be for the betterment of our mental health and is a great conversation starter. :beerchug:


Sounds like ya got a good head to know how to sift through the information instead of allowing the craziness to control ya, which is a very healthy thing. :claphands:

 

[HTH]

Did you miss the part where I speculated why the top turn is ineffective. Anything gained in the turn is soon lost as the water pulls the particle to its speed on the way down ?

Conical or other expanding cross sections are better choices then other methods of slowing down the water. Less turbulence and they do not waste pump power by reducing flow. We want to preserve flow when we slow the water by going to a larger cross section.

For the short term I think we should forget about buckets and barrels and other physical things at hand and look just at what would be ideal. Then we can down grade it to fit the real world.

 

[HTH]

Litzi1964

There is so much variation in ponds that these rules of thumb are next to worthless.

Not too long ago we talked about ponds without any mechanical filtration and in their own way they work too. River 'ponds' are at or near the other end in turns of turn over. So there is not much point in these rules.

What is important in having a system capable of supporting the bio load. I say bio load instead of fish load because things like decaying plants also contribute. In short we always have to ensure that we are not overstocked.

Anyone with the ability, space, and the water can build a pond. Budget and scrounging will dictate what it looks like and how large it is.

 

[crsublette]

Oh, the point in the "general rules", as applies to any generalities, are to help folk avoid making some bad mistakes at the very begining. These rules are much like a "Stop" sign. Will ya get in a wreck with every "Stop" sign you ignore?? Nope. Does your chance significantly increase to wreck from ignoring the "Stop" signs?? Yep. Now, some folk's "general rules" are like puting a "Stop" sign on a deserted county road where absolutely nobody has driven for years, but yet the roads were used once upon a time.

 

[crsublette]

1) Did you miss the part where I speculated why the top turn is ineffective. 2) Anything gained in the turn is soon lost as the water pulls the particle to its speed on the way down ?

3) Conical or other expanding cross sections are better choices then other methods of slowing down the water. Less turbulence and they do not waste pump power by reducing flow. We want to preserve flow when we slow the water by going to a larger cross section.

4) For the short term I think we should forget about buckets and barrels and other physical things at hand and look just at what would be ideal. Then we can down grade it to fit the real world.

1) Did you miss the part where I speculated why the top turn is ineffective.

Read your posts many times over to try to understand how you are expressing the "top turn" idea. It is a bit tough to follow. I think I understood the points made about the cross sectional influence on the linear speed.


2) Anything gained in the turn is soon lost as the water pulls the particle to its speed on the way down ?

Yep, that is why retention speed was mentioned and how the velocity of flow rates have a dramatic impact on these settlement chambers.


3) Conical or other expanding cross sections are better choices then other methods of slowing down the water. Less turbulence and they do not waste pump power by reducing flow. We want to preserve flow when we slow the water by going to a larger cross section.

Yep, that's what I figured and why I expressed why we are trying to reduce the water's velocity, or turbulence would a better word, so to not reduce flow rate.


4) For the short term I think we should forget about buckets and barrels and other physical things at hand and look just at what would be ideal. Then we can down grade it to fit the real world.

Sounds good. Sounds like you got the better grasp on fluid dynamics than anyone I have ever read in regards to constructing the better settlement chamber, which is a compliment.

What do ya have in mind that would be practical and could be "down graded to fit the real world" in our context ?? It sounds like this is not an easy question to answer. I will be very interested in reading the answer when it comes!! :claphands:

 

[HTH]

What do ya have in mind that would be practical and could be "down graded to fit the real world" in our context ?? It sounds like this is not an easy question to answer. I will be very interested in reading the answer when it comes!! :claphands:

This is the idea I want to play with next. Fortunately it can be prototyped with standard pipes.

Having said that moving water horizontally so the solids can settle seems interesting. To test this idea I am thinking of stuffing the first foot or two of a 4 or 6" pipe with thin wall 1/2 or 3/4" pipe to reduce the turbulence then using the rest of the pipe for settling. Split the output of the pump between several of these. To flush one would just turn off the water to all but one. A slight rise in the direction of water flow might help the solids to stay put and ithe final version could be underground if we have enough flow to flush the solids up.

I see this as a lab to experiment with linear speed and length required. Wondering if a square cross section would be better.

We have had some spotty rain for the last hour. Looks like it may be headed your way if it does not slide too far east as it goes south.

.

 

[crsublette]

Sounds like attempting to make a laminar water flow with the pipes to reduce the water turbulance. Interesting idea. Makes sense.

I'm curious how this will be done by not increasing friction loss due to all of the splitting of pipe, but, if using 4~6" piping and adaptors, for the entire settlement process sounds expensive, then I would figure friction loss would be irrelevant.

Yeah, this is going to have to be something for me to see to better understand.


Heck, it does not rain here. It only hails and blows like hell. There always seems to be an odd horse shoe maneuver when storms near the area.

 

[HTH]

Looks like the rain is still on track for your area. My rain gauge is saying 'not much' but when I went to check the lifts to see if the GFI had cutout I feel flat on my rear. Darn clay is like greased snot.

Yes laminar flow. One is going to incur some friction but if thin wall PVC is used it will not be anything near a solid plate drilled with holes. I hope it is a step in the right direction. Thin wall PVC uses less plastic then schedule 40 so it is also cheaper. We really have no idea on the cost till we know how much pipe it would take. To cut costs we could consider used pipe. The diameter is a catch 22 thing. The larger the diameter the long it needs to be. Which has me thinking, I have a large stash of thin wall pipe. I wonder how it would work to stuff the entire length of the larger pipe with smaller pipe? The longest distance for a particle to settle would be greatly reduced so the pipe could be shorter, maybe much shorter. I know I am talking out of my back side but then that is what brain storming is all about.

I was in Dalhart yesterday to see the dentist. A few miles north of town I seen top soil headed east on the west side of highway.

 

[HTH]

Rain was only enough to just show in the rain gauge. It was slippery beside the pond because the canopy over the pond contributed.

This morning I replaced the 700gph pump on the barrel filter with a 1600. The flow was enough to totally over power the hat's ability to collect solids. It will be interesting to see if they end up in the bottom of the barrel or in the quilt batting following the barrel. I may have to split the pump output and run some of it unfiltered back up to the top lift. Such fun.

 

[Litzi1964]

Are perchance any of you gentlemen engineers by profession? I showed this thread to my husband, who is an engineer. I was mindboggled. I am a mental health therapist and my background is clinical psychology. So I can tell you all about classical and operant conditioning, associative learning, group social dynamics and so on, but I couldn't have been more baffled by Charles' setup if he had described it in Chinese.

While cost is certainly an issue, simplicity is an even bigger issue. When I set out to do the pond, I made it clear to my husband that it would be my project and my hobby, and I'd only solicit his help when absolutely necessary.

 

[HTH]

Litzi I was an engineer but not a mechanical engineer which is what would be needed on this problem. But i did study physics and have some idea of what is going on. I expect a mechanical engineer might scoff at my experimental approach.

Simple is good. We often talk about KISS (Keep It Simple Stupid). But simple has to be based on good design. On ideas that work and what the right application of that idea is.