Settlement chamber after pump?

[Cdsdave]

Hi all! I have a question about settlement chambers. My pond setup is 2000 gal with a bottom drain and skimmer. I have both of them meeting up at a jandy valve (2in PVC) leading to a 4000gph pump. The distance from the jandy valve to the pump is approx. 2ft. From the pump its about a 10 ft run to my 4000 gph tetra pressure filter, then a soon to be installed UV, and finally to the falls.

I know ideally an SC should be before the pump. However when I built the pond an SC was not on my radar so I didn't really allow room for it. I was wondering if its worth it to put one after the pump? If so what size and plumbing scheme should I use? I would want to do a DIY chamber. Any suggestions?

Thanks !!

 

[Waterbug]

Define "worth it".

I don't personally see much benefit to a SC anywhere. Way better options today imo. But people do still use them.

First off, BD and skimmer tied into a 2" pipe is asking for trouble. Chances of string algae clogging there are about 100%. People do tie BD pipes together but at a place where clean out is doable. The Jandy setup doesn't sound like it would be fun to take apart to unclog a couple of times a day during a string algae die off. Generally a 3" pipe is considered a minimum. There are mass market type BD with 2" pipe but those are only to make selling easier, they don't actually work when you need them.

The "worth" of the SC is kind of relative. The design of the tank I'd say would have more to with increasing or decreasing worth. The pump will grind up poop but ground poop will settle for the most part in a good SC. I personally have never actually seen a good SC. I've seen many SC on Koi tours over the years (they used to be very popular) and the owners would say how great they worked, but the pond told a different story. Owners often see what they want to see.

If the pond is above grade even a couple of inches you can use the pond as a SC. Instead of flushing the SC you flush the pond. It's exactly the same thing.

If below grade you'd need a waste tank and a pump for that too.

That assumes the BD pipe is 3-4". If that pipe is 2" I wouldn't worry too much about it because chances are at some point you won't want to deal with clogs and just close it off.

 

[Mucky_Waters]

I wouldn't bother. Settling chambers work best when they are gravity fed, putting the pump before the SC defeats it's purpose on a couple of levels. (1) the pump blends up the dead algae and fish poop before it has a chance to settle out in the SC. (2) a SC is a great place to capture small fish and what not that get sucked through the bottom drain, before they get sucked into the pump or the rest of the filter system and are killed.
Here is a video of the biggest load of critters I scooped out of my settling chamber

I routinely have small fish get sucked through the bottom drain and end up it the SC where I scoop them out with a net before flushing it out. It's a great safety net.

 

[Waterbug]

When fish poop breaks most of the pieces will settle better because gases are released. However, there's still even smaller bits so there is a trade off. Depends on a specific pond keeper's goals.

 

[Cdsdave]

My BD is 3 inch. From it I connected a 2 ft. Section of 3 in. PVC. In hindsight I would of run 3 in. up to the 3 way valve, however I connected 2 in. from there since I installed a one way valve (which was two in). I was told to make sure the one way valve was at least one ft below water level so I made it about two ft below. I used two 45 degree (instead of 90) at all bends to increase flow. The Jandy valve can be unscrewed from the top in case clean out is needed.

I haven't had any string algae issues. The two in PVC from my skimmer is clear from what I can feel( not too far) When I shut off the skimmer and just use the BD, I notice no change in flow. When I clean out the pumps leaf basket I find it rather clear. Just small twigs and some algae growth.

Thanks for your input!