A bell siphon usually dumps all the water from an aquaponics grow bed. It does this by creating a siphon once the water gets to a certain level.
The cool thing about it, is that once triggered, it lifts water up and over a standpipe, and does this until the grow bed has drained. This gives us our flood and drain cycle in our grow bed.
It seems constant flood has some advantages.
A constant flood system holds more water, so might be a bit more stable. Whenever anything changes in a system, having more water means that it tends to change more slowly. There is also probably a bit more real estate for the micro beasties to live in.
Most plants don't seem to mind so it looks like a thing worth doing on at least some grow beds if you have more than one.
I only have one, and its very stable, but my fish are getting bigger, so there might come a time when I'm running my system a bit closer to its fish holding capacity. With this in mind I'd like to maximise my system's ability to deal with the extra load.
One possible problem with constant flood, is that over time it might be more likely for areas to become stagnant. Constant flood pulls water from the top. If you are adding water to the top and taking it from the top, the water might ignore your desire to move through the system, and just take a short cut straight from the inlet to the outlet.
A system using a bell siphon drains in a fairly dramatic fashion as all the water is dumped, often a lot faster than it went in. This sucks a lot of air down into the media, and also creates a powerful surge throughout the system. The strong surge might help to distribute solids away from the water inlets, spreading them more evenly through the grow bed. A siphon pulls water from the bottom, and this might also aid in distributing nutrient evenly.
Constant flood = good
Flood and drain = good.
I hate the way the universe can do that sometimes. Make up your mind universe.
In an effort to greedily get the best of both worlds, I have changed my siphon a bit.
calibrating a new bell siphon)
This means you system can be stuck on empty.
Plants and bacteria hate that.
If your plants and bacteria aren't happy, your fish are miserable.
When the water level gets down to the breather pipe, it suddenly sucks air and stops the siphon. Basically it just makes the siphon a bit more forgiving.
What this means, is that we can mount that breather pipe further up the bell, and when the water empties to that level, the siphon stops.
So now we can have a situation where the only 20% of the grow bed is drained, but it is still drained with a powerful surge, and it also still drains from the bottom. This may well provide a decent compromise.
I have a feeling plants will enjoy having their feet always wet, but their knees in flood and drain.
I'll let you know if anything terrible happens.
Things so far...
Animation (5) Aquaponics (339) Bread (15) Cheese (15) cooking (49) electronics (57) Epic adventurer (20) Escargot (2) Fire (6) Fraudster (1) Handmade fishing lures (31) Home made preserves (11) Making smoked foods (11) Mold making (7) Movie watcher and critic (2) Photography (17) PVC (36) Snail farming (6) Solar hot water (26) Solar photovoltaic panels (7) Stirling Engines (11) Thinking (49) Vermiculture (1) Wind energy (25)
The bell siphon was a clever thing for someone to design, and as such you feel a bit of that "clever" rub off onto you when you m...
You see CHIFT PIST a lot in the aquaponics forums and it means "constant height in fish tank, pump in sump tank". And its a very g...
A "bell siphon" is a device that automates the flooding and draining of an aquaponics grow bed, even though the pump is adding wa...
Painting lures is easier if you don't know how. I don't, so I'm already well on my way. I started by owning a printer. That ...
A while ago I tried to make a fish fed fish feeder design that would allow the fish to feed themselves. I think It's made. I say &q...
Apparently, marron come in two varieties. Hairy and not so hairy. Cherax cainii (smooth) and Cherax tenuimanus, or Margret River marron (hai...
In aquaponics, one issue that can effect your success rate is the pH of your water. pH is a measure of water's (or soil's or whateve...
With a little practice its possible to make a screw. If you bend your wire into an eyelet, its possible to make a screw in eyelet. The use...
I had an idea, but now I'm not sure it was mine after all. But here it is anyway. I need to get solids out of the water for the NFT, ...
This post is a follow up to the " handmade fishing lures how to get most out of your printer " post describing my way to colour ha...