Before you send water to your NFT pipes

[TCLynx]

FILTER IT

Yes that was me shouting.

What's NFT, that would be nutrient film technique or when you put the plant cups in holes in a pipe or trough and trickle a film of water along the bottom of it.

An aquaponics system is more than just fish and plants, if you try to do aquaponics with only those two things, you are sitting on a two legged stool and something is bound to collapse. The most important part of aquaponics is the filtration.

So, before you send water into your NFT pipes, you must filter it.
Now that doesn't have to mean anything fancy really, but you will discover quite quickly that if you send dirty fish poo water straight to your NFT pipes, they will get really gunky and the roots get covered by globs of fish poo and it can even get nasty and stinky enough to make a person gag if the system is heavily stocked and the fish are being fed well.

My initial attempt at NFT with aquaponics just took a feed of water from the pump that was drawing from a fish tank. Started out OK for the first few days but within a week, it was not so nice anymore. It seems that catfish and tilapia poo along with the remains of floating fish feed creates quite a light slimy glop that will coagulate together and stick to roots and wicks until disturbed. GAG
So scratch that first attempt.

My current system has a clean water sump tank, that is the water that makes it to the sump tank has all gone through some sort of filter before it falls back into the sump tank. The filters are mostly my flood and drain gravel beds. Since there are no fish in the sump tank to poop or be fed and all the water from the fish tanks goes through gravel beds before getting back to the sump tank, it is a clean water sump and that filtered water is fairly good for use in NFT pipes provided algae is kept at bay and the feed lines to the NFT pipes are big enough not to get clogged by simple bio-slime.

I've seen several instances where people wanted to make a system where they simply pump from a fish tank through several pipes growing plants and several more times where that is what they had set up. The questions range from "why are my fish dieing?" to "why are my plants not growing?" to "aquaponics stinks, this is crap why do you people keep saying it's great?" All that because they skipped the filtration.

Think of aquaponics like a triangle
Fish, plants, filtration (the bacteria of the bio-filter and the mechanical solids filtering)

[TCLynx]

Here is the only Commercial Aquaponics system I know of at the moment that has a heavy NFT contingent.

Green Sky Growers

Very high tech and loosing money, they have just been sold to Aquatic Eco Systems last I heard.

 

I don't have any designs or drawings for such systems but you will need filtration to make it work.  I would recommend perhaps doing some research into bio-filtration and solids removal like is used in high density Raft systems Like at the UVI or aquaponics.com

Otherwise go to Aquatic Eco Systems and look at some of their solids removal and bio-filtration products.

 

I'm not running commercial and my two NFT pipes are just add on bits to my big system and are rather underutilized most of the time.

[BenHehle Beamz]

Hi TCLynx, could you give me more details about the sump and the filtration? you have any sketches or pictures of professional or commercial NFT systems? we try to rebuild a nft system with AP at university (i would more like to build one with growbeds and gravel, but the old nft system from hydroponic has no use at the moment, so we want to use it for AP)...for every information im very thankfull.it would be great to hear from you :D cheerio Ben

[TCLynx]

Just remember to check the pipes often as some plants will fill them with roots to the point of blocking and overflowing. Tomatoes are known to do this and tend to require root pruning in NFT unless the pipes are gigantic.
I also expect that cucumbers could throw out a large root mass if they grow long enough (cucs never seem to survive for long for me, probably due to my high system pH.)

Even with basil and most other things, checking inside the pipes often is a good idea and root pruning as some things start getting overgrown.

There may be many Asian greens that will do better with heat than most of the lettuces we usually think of. Nate recommended india mustard to me but it is a spicy one I guess.

[Knowmore09]

Thanks! TC.

Seen people do cherry tomatoes and cucumbers. They just put the pipes up on cinder blocks and let the vines flow down on the ground. Strawberry of course is the all time favourite of NFT, but alas! not in my weather.

The 6 metres that I have is in 1 mtr pieces. So no worry on the heat build up and loss of DO.

So basil, Cukes, Cherry toms, red and yellow peppers it shall be. I will also try out some spinach, coriander /cilantro, eggplant and parsley. The monsoon has just started. So won't see very hot temps till End Jan.

Will keep you guys posted.

[TCLynx]

Ya know, I haven't actually really grown all that much in NFT. I've got a couple 15 foot long runs of 4" pipe.

Of course in our short cool season, lettuce and most all small greens do great in the NFT but we have much more hot the cool here.

for the Hot season, Basil is my stand by for the NFT pipes
Another lesser known plant that likes the hot season is Purslane which I have grown quite successfully in my NFT pipes.

I have managed to grow peppers in the NFT since they take so long to get going, I kinda like starting them in the cups where the little seedlings are less likely to get smooshed by indiscriminate digging in the grow beds.

One issue to keep in mind in hot climate with NFT is the longer the run, the more heat build up there will be in the pipes and the more depleted the dissolved oxygen will become.

[Knowmore09]

Great post! Thanks! As usual you hit it RIGHT on the HEAD! Maybe in the next one you could tell us which plants do best in NFT, best pipe sizes etc! Most NFT's like Rupe's that seem to really thrive are the planted ones with lettuce. Unfortunately my climate doesn't permit that. Max Temps here are over 25C 10 months of the year. I have a 6 mtrs of 4" pipe with 36 holes all drilled and ready for plumbing. Have been pondering on what to plant.