Backyard Aquaponics
A place to discuss aquaponics

Sorry for all the questions however, I was wondering if the placement of my bell siphon really makes a difference or should I split my grow bed up. My grow bed is 16X4 ft and 1.8 ft Deep, with a grow bed this large what are your thoughts on having a single bell siphon verse splitting it up into multiple bell siphons? And would anyone be able to recommend a size for the standpipe?

I think if you have multiple siphons in one bed you'll run into problems - even if you get them as close to the same height as possible, they won't trigger at the exact same time. Either you'll get just one running, in which case there's no point to the others, or you'll have a couple dribbling and they'll never kick off to siphon properly because they'll be splitting the water flow between them.

If you're talking about splitting the grow bed up into separate beds that operate independently, though, yeah that'll work. XD Not sure what the optimum or maximum grow bed size is, but I asked on a different forum about the pros and cons of one big bed versus multiple smaller beds and got told media beds over 5m long (about 15 feet) won't drain properly using bell siphons. People also pointed out that multiple smaller beds are a lot more convenient to move, clean, or otherwise mess around with when something goes wrong. So my vote is to split it into multiple beds!

I'm sure somebody can give you better info than I can on specific standpipe sizes; all I know is that it needs to be big enough to draw water out under gravity faster than you're putting it in even once it's drawn the water level down and is working against a slight head, but not too big or it won't start. I totally guesstimated to start with and have tweaked things through trial and error since. I do recommend using a reasonably sized bulkhead fitting as the base, and then you can change the standpipe and drain piping underneath around as needed using adapters / reducers / etc. DEFINITELY make your media guard big enough that you can comfortably get your hand into it even when the standpipe is in!

Thanks for the advice, i'm going to split my bed into two 8X4's for better convince

My biggest bed is 3.4m x 1.2m, and it only has one siphon, and it works fine.

You just need to size your bell and standpipe to the waterflow. I've got a 40mm standpipe - 90mm bell, I'd say you'd need to double that if you're trying to put twice or three times as much water through it.

Two in one bed would be a nightmare.