Relative sizes of inflows and outflows

[Louise]

I'm setting up my first greenhouse-scale ap-system, you might have seen other threads about it. 

I bought a more apropriate pump, and arranged so I can modify the flow rate.

Now I need to modify/add the sizes of the different plumbing parts.Now I think that the grow bed drains back to the sump too slow, and probably the fish tank needs to drain to the grow bed faster too.

So-

1:If I get a bigger pipe out from the fish tank, the availability of "T" pipes might force me to change the size of the solids-lifting pipe - what's the maximum size for that to still function?

2: For different reasons I can't make the bottom drain from the GB to the sump bigger, but I can add one. Currently it is a 32 mm standpipe with small drainage holes at the bottom. My plan was that it can easily be replaced by a Flout or a bell siphon if I choose to, since I left a reasonably large space without media there. I won't be buying a Flout from the US, as the shipping costs to Europe are ridiculous, but I might try to build one. -Anyone had success making your own? Find a flexible enough pipe?

 I could supplement the current standpipe with either another standpipe the same size, or, I'm thinking, does it make sense to supplement it with a bell siphon or a homemade flout?

Do any of you use more than one type of emptying device in the same grow bed? Experiences?

[Fred]

I'm building a system about this size as well using a single IBC for the fish tank and barrel grow beds.  The size I'm planning to use is 2 55 gallon tanks (on their sides) as a sump.  The fish tank is 275 gallon and I'll use another 55 gallon barrel for a swirl/settling filter.  Currently, the plan is to setup 4 grow beds using barrel halves and expand from there.

My plan for the solid lifts from the fish tank is to use 2" pipe with a tee on the bottom to split the lift on the bottom of the tank.  I'll stay with 2" pipe from the fish tank to filter and then filter to grow beds where they'll be reduced to 1" or 3/4".  I have a single 1,000 gph pump which should cycle the entire volume twice per hour (not factoring in the reduction due to lift).

 I'd love to hear some feedback on solid lift sizing.