Backyard Aquaponics
A place to discuss aquaponics

has anyone investigated a capillary action NFT? my basic idea is that the material you use to filter your water draws the water up via capillary action and wicks it into the NFT run, which returns it to the fish tank.
no pumps needed.

Does the capillary matting run down the nft as well, or stop at the top of the run?

i'd stop it at the top of the run so the plants roots don't invade it.
then again you might want that?

Don't know if it would return the water to the system. Need a picture. I've seen capillary action drain a container. But running up and then back down. Maybe have the wick draining a tank down through a NFT into a sump that you can then pump back up to the higher tank.

The water will not run up the matting, leave the matting and then run down the nft.

Not last time I checked anyway.

Thats how my drippers work. Not a great flow, 1 ltr a day on a strip 30mm wide. Thought he was going to have the mat the length of the NFT.

Hi Tim
Its good to think outside the box. I`ve looked into using capilliary matting for vertical nft.
Dave (DD) was also testing something similar with his planted veggie wall.

Heavy cap mat material will wick upwards but not very far (100-150mm).
The main benefits are the safety net it provides for power outages etc and the distributed water spread across the mat. The cap mat i bought for test purposes holds 3.5L water/m2.
The downside is roots do invade the capilliary matting and can be impossible to remove...welcome to the world of ever decreasing circles

Something like perlite will wick upwards but the capillary action wouldnt provide any flow for the nft as it will moisten the media and then stop

In the Autopot window box's they use a mat with the pots sitting on top of it. The pot have root mats to stop the root from going any where. Could make something to sit on the FT surface with pots sitting on it. You would have to cover the mat from the sun.

Wicks and capliary matting might have their uses but I doubt they can take the place of gravel beds and pumps.

Very true.
Capilliary mats are probably very effective biological filters (large surface area, a thin film of water and plenty of O2 contact)
No pump needed if its installed around the tank water level height.

Unfortunately the only flaw is its a one-way street and they don`t allow any of the clean water back to the fishtank

But if it's a one way street into the plant then if might be okay.

right but the one way street even if it is to a plant kinda defeats the whole idea of the bio-filters and plants cleaning the water for the fish.

I admit that some use of the water that way (strait to plants/no return) is probably ok, especially if you would be needing to do regular water changing anyway because your Nitrates are off the charts and you don't have enough plants to suck them up, but in the general initial system design, I don't see it.

I think I've got the idea of what you guys are talking about. Won't a cloth siphon water out of a glass as long as the bottom of the cloth is below the level of the water. Just like any other siphon except no sucking required, it would self start.

If you had a header tank above the NFT gutters and some sort of matting or cloth from the header to the gutter that would work. You might need to replace the matting regularly as it got clogged but the water provided to the NFT would be really well filtered.

By Stuart I think He got it!

Actually I don't think that was the original intention of the idea first mentioned, but......That would be the way to do it. It would still require a pump some where in the system as well as a bio filter and a way to remove solids so they are not sitting there rotting but that would be a way to have a nice slow drip of solids free water into an NFT trough or anything I suppose and then let the NFT trough drain back down into the fish tank or sump.

Cool idea there. Hum, I might actually have to try that. It wouldn't have to be capilary matting actually, since I know that nylon stockings will drain a cup of water onto the tabel if you are using them to tie up something you are soaking and you leave the loose end hanging out of the cup.