Thread: Pipe work Qs

Originally Posted by CobraKoi

Starting to think about my pipe work (hur hur hur).
Plan is

4" soilpipe from the bottom drain to the filter house.
I've one joint to make underground (straight coupler solvent weld) , will 4" push fittings work in the filter house above ground?

2" from the skimmer to the filter house.
again a few underground joins but not worried about them.

Then I have 2 x 2" returns ,
These returns will be long....somewhere between 12/15m
Are the returns too big ? there is very little head height - a pair of DM varios (10k,20K).

Any advice welcome

the 4" push fit soil will generally work, but consider how much hassle it will be to swap if you get a leak....
but solvent weld and/or rubber boots would be better after a solvent welded valve.

that run is long, and will incurr friction losses.
how much depends on how much water lph you want to put through it...
but i'd err on the 20,000 varios as they have a bigger head height than the 10,000's that helps over come the losses.
what size pond?

Thanks for the input.
I'm thinking push fit because I will 100% be chopping and changing equipment .
What about the 2" returns , am I worried about nothing there ?
Returns will be just under the level of the water .

Edit - not sure on final size, 20/25k L
I bought the 2 pumps years ago when someone posted a bargain alert here so I have them allready.

Will the 2" help me or work against me ?

Could also go flexi rubber boots which give a good seal on both pressure and solvent weld pipes plus you don't have to be spot on with the angles of things going together like you do with pvc pipe. Quite expensive though but also quite adaptable. I've used them to hold 2" slide valves onto 2" and even 1.5" pipes. Just make sure you get the right ones as some are not UV stable. I've found Fernco are the best ones and Flex Seal are the UK branded version of the Fernco ones which are American I think? The Evolution Aqua ones are pretty good too.

From what I've seen on here if you go 4" in you go 2" out.

On my 2 systems though I've gone 3" in and 2" plus 1.5" out. There's also bits of 4" in both of my systems too as it's a bit of a Heinz 57 set up on them both

Originally Posted by CobraKoi

I probably over thinking it

Do you need to push mesh on the returns to stop anything swimming in there ?
Small fish/frogs etc ?

Good question lol

If the returns are above the water level it would stop any fish getting in there apart from if they jump out of the water into it but frogs etc could climb into them. If the returns are under the surface then a lot more could get into them. You can get plastic strainers that go into or over the ends of the pipes.

What would be more of a concern for me would be a small to medium sized fish getting wedged into the end of the return if things kick off during the mating season

This is what I was thinking about

https://coastal-koi.com/product/filter-cages/