Backyard Aquaponics
A place to discuss aquaponics

Yep, B has them in the plumbing section, I use the 40mm version, they are called a "40mm pug and waste", cost about 8 bucks I think.

Ok, was just up there, just on closing again! Dang last minute rushes I've already cut the 50mm pipe and it's not like I can return 270mm lengths and ask for a refund I'll just cut my loses and go with what I've got, no big drama's I can still get in there to clear it out if needs be, but will definitely go that way for my next system

Heres the 3 stand pipes i use

As usual... looks like I over engineered things

Nope you over complicated it. Over-engineered things are easy to use and work well, but at designed to withstand much more than will ever be asked of them.
Sorry - pet hate of mine, (see my signature) ppl keep taking it the wrong way

Think that's exactly what he meant Kuda

Hmm whoops, may not have read it right, I thought his design did not allow easy root removal... my bad, sorry. :-)

Hi kenour. If ur standpipe is removable, just drill one 6mm hole at the base of each to start with. If u decide to add yet more beds down the track, it will mean ur existing pump will cope bc u only have one drainage point per growbed instead of 2 if u drill 2 holes. It will give u a longer drain time which provides a longer period of aeration for ur fishtank. U can always drill another hole later if for some reason u decide u want a faster drain time.

I was thinking about that, just means I have to drill the outlets higher (above the joining bit), so there will always be about an inch and a bit of water in the bottom (got a design to fix this and control the flow rate ), but then again, when you look at the APA trough, it has the two ridges, so the two divisions without the drain hole will always have a bit of water sitting in them! I don't know if this will be a problem, as it'll be disturbed every hour when the pump fires up?

If the water was sitting for extended periods there may be an issue. (Build up of anoxic conditions leading to hydrogen sulphide, nasty stuff.) With AP we always have water flowing thru and most of us have some water in the gbs at the end of the drain cycle. I wouldn't be too concerned. Ur solids will settle out and congregate, so when ur pump cycle kicks in, u won't get that cloudiness u speak of, (once ur system is properly cycled, there is the pea soup stage during cycling which is normal.)

Sweet as then

Just one more quick one about the stand pipes! 6mm seems to be the common wisdom for hole size, and it has been suggested here that I have 2 x 6mm holes to increase drain time if it's too slow.

So just wondering why 2 x 6mm? Would I just be able to get away with 1 x 9mm hole instead? Or is it too soon for radical thinking like this in the AP world

Think the idea was to put in one 6mm hole and if that was not large enough, then add a second...options are:

1) put in 9mm hole
2) fill 9mm hole if too large
3) put in 6mm hole and add more if required

9mm will add more flow than 2 x 6mm holes, so it depends on how quick you want the water to be removed

I managed to solve all my problems with this

Good one kenny. Now the challenge will be seeing where the holes are once the fitting is in the bed. Suppose you could feel for it and mark the standpipe top to show where those ones are :-) Good idea buddy.