Backyard Aquaponics
A place to discuss aquaponics

Am excited about the prospect of setting up wicking beds and using the enriched AP water for it.

Then I thought, wait, I salted my FT to around 3ppt and when I dump that into the wicking bed resevoir, wouldn't that mean that I'm introducing salts to the wicking bed system?

And if I'm topping up the resevoir with the AP water periodically, the concentrations of salt in that resevoir would also increase over time.

As the wicking bed resevoir only has an overflow for water to exit, and none for the discharge of the resevoir to evacuate the denser salty water, the salt concentration will continue building up in the wicking bed over time (is my guess).

Is there any concern with this in the long term for the wicking bed and productivity of it?
(or am I just a purist chasing after shadows)

I've built my wicking bed so i can drain it off the bottom and set the water level externally so i can flush the system if needed

Me too

Yes I would be concerned.
Redesign as others have said
I have.half barrels with small hole 150mm up from bottom - works great.
When I used cocopeat as a wicking medium and dug through the potting mix, I found slow growth maybe because the coco has a possible wash from salt water.
The overflow hole on this pot had more white sediment set on the runoff pattern.

thanks for the responses.
I'm planning to put these 'wicking beds' in the ground (with about 100-200mm raised above the ground level), so will have to figure some way of putting some access hole at the bottom though to allow the beds to drain away under the natural ground level.

Never that simple for me I guess

I'm adding two half-barrel in-line wicking beds to my system this week for testing. Continuous flow through lava rock on the bottom, then landscaping fabric with soil on top. The system is covered, so I don't think I'll have issues with liquid seeping into the AP water from the soil.

the wicking beds i was thinking of were to be entirely separate from the AP system. I was just going to use the AP water (as part of any water change) to feed into the wicking beds.

I wasn't too keen to have wicking beds 'in line' with the AP systems (as some of the members here have done)... not experienced enough yet

I run my AP system at 3ppt and I use it to fill my wicking bed. Cant see Ive seen any problems and its been cranking along for about a year now.

There you go, thanks Charlie.
Maybe a flush of different water every now and then?

No probs jay,
Im still learning the whole wicking bed method but I think it would be a good thing to change the water out every 6 months or so. Maybe F&F will chime in and give advice.

I havnt changed mine yet because Ive been waiting for it to smell, which it doesnt so far. Maybe the salt helps with that too?

My thoughts were that the soil around my area is very salty anyways and plants grow well in the garden so cant be too bad. Also my AP [plants grow ok in 3ppt salinity. Its not really what you would call salty though.

Cheers

The problems with wicking beds should only come from evaporation and the buildup that will occur with that.
It could take years at 3ppt to really have an effect, if you have a problem, try find a small "saltbush" or similar to help suck the salt up for reuse.

I have wicking beds and think they are great way ti grow but is it really worth integrating them with AP?

Recently I had some talking to me about using all wicking beds as the GBs and flushing the water underneath and back to a large pond. This was concept only...
Does anyone have experience with this?
Would it work?

the earthen beds (aka ap wicking bed)work like that with media in the bottom and a stand pipe to prevent the water flooding to the soil level.

I think soil has a lot going for it. People have been actively working with it for 10,000 years or more, so I think it has a solid track record. Subsurface irrigation with nitrate-charged water does seem like an improvement, though.

That does sound like an awesome concept - best of both worlds and you could prevent/manage the salinity because the water would be circulating through.
I'll have to start researching and give it a go when I move back to some arid country.