Aquaponic Gardening

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Hi all,


this lettuce is about 4 weeks old.  they were doing ok, until its lower leaves started to seem to rot away. I'm pretty sure it is because i have not filtered the water going into the PVC holding the lettuce. It can get quit gunky in the roots, which i wash out with tap water on occasion. I can find some time to hook up a filter to the system this weekend, but i was wondering if i did... can the fungus be cured? or is it ruined and i have to start over?


thanks much.


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If you are pumping fish poo right into those pipes without any filtration, I expect you will have trouble with many of the plants being stunted with their roots starved for oxygen and nutrients because they are all gunked up.


Do you have any sort of filtration on that system?  What do your water tests say?

I expect if you get the plants into a cleaner well aerated situation, then you could pick off the bad leaves and you will probably have something to make a salad with through it might not be marketable.  But if you can't get the filtration hooked up, I expect you will have more problems than ugly lettuce very soon.

For NFT systems you need a clarified were all the solid stays and a bio tank or filter, the PVC pipes are to slick for bacteria to build in it, Check the pictures on my page My system is a raft but the filtration is very similar in what you need. hope this helps.

thanks for the response


my plan is to filter with a simple pre pump filter sponge - on the intake for the pipe.  will that be enough? i would wash out the sponge daily.


i'm glad its recoverable.. i will filter as of this weekend.


i honestly don't test water... yet.


there is no filter yet. i have a 200 gallon tank to install which will contain bio balls. its sorta a hobby thing and i do work on it when i can...and have the money.

How many fish do you have?

A sponge filter won't be enough.  If you find your roots are getting gunked up regularly, a sponge filter will probably be getting all gunked up and cause overflows in less than a day.


If you have any fish going, you need some filtration.  I would say stop feeding immediately and don't feed again until you get a test kit and see whats going on in your system.  Your plants could be suffering from a lack of nutrients because you don't have any filtration and your ammonia is building up and there are little/no nitrates for the plants.  Your ammonia could be high, your nitrites could be high and your fish could start dieing on you.

ahhh the sky is falling!... :-)




The supply to the lettuce will come from a separate pump- inside the sump. it will have a pre sponge filter. i dont see how it would overflow? the worst that could happen is the pumps flow decreases. would the filter be sponge be enough?  to remove fish poo and solids?




i'm about to check Claudio's filter. as i  have been researching what i need... and havent come up with much so far.


thank you both for your advice.



i have about 100 tilapia in each 4 of the ponds.. the other 4 are just circulating. each pond is 2000+gallons. the only water movement is circulation and an air stone each pond. Also vast amounts of rain water. the system is continually being upgarded. i have a sweetwater blower to install, a huge bio filter... and i guess a main mechanical the future.

Ah, ok.  It wasn't clear that you have a bio-filter.


It sounded like you were wanting to put the sponge in the start of the plant tubes or something.  The sponge filter on the pump is gonna clog up fast and it could be hard on the pump but it might help your plants a little though you are going to be cleaning that often.

Just build a gravel bed upstream of your NFT and let it filter for you. Your lettuce can be saved by pulling all the dead leaves off and spraying the lettuce with a solution of baking soda and water and let sit over night. Rinse off the next morning. Mix 1/4 cup to the gallon. It will wack any fungus. You must rinse the leaves after 12 hours to get the salts off. I cant see what your roots are like but a good rinse will help them. Spray with a nozzle to blow off built up fish shi= .

thanks guys. this is really helpful...


i like the homemade solution.. will try it....


what size gravel works best? for filtering poop?  - 3/4" and 3/8" is what i have available...

how much length- assuming i'm using the same 4" pipe.. do you think will be enough for the gravel filter.. i will still pre filter with a sponge on the intake..



Actually I would say get a mortar tub and set it up to filter before the water goes to the pipes.  Use the 3/4" gravel assuming it is not limestone gravel (test with vinegar to see if the gravel fizzes to see if it will give you pH issues.)

You might need to brace the sides of the mortar tub but it will be a start for a gravel bed and you can put a few plants in it too.


I do not recommend putting gravel in a pipe.


Another option might be a trash can with gravel set up on something so you pump into the bottom and the water flows up through the gravel and flows out into your plant pipes.

TCLlynx.   with 3/4 gravel in a tub barrel the size of a large garbage bin... what would my maintenance be like? in terms of needing to wash out the gravel?


i have an empty 50 gallon i'm eyeing for this gravel filter...



It will all depend on your stocking density.  I know people who have had ponds with upwelling gravel filters run for years without any special extra maintenance and other situations where you might want to flush it every month or so.  So just in case you might want to plumb in a valve down at the bottom so if you ever need to drain the thing and flush/rinse it out you will be able to.  I guess it would be like backflushing most any filter.  I'm not running any filter like this myself so I'm not an expert.


My system is mostly gravel beds and they take no extra maintenance, they are the solids filtration, bio-filteration, and plant growing space all in one and I can seed directly into them and they also make a great worm home and don't require any extra aeration.  They are really rather boring if you prefer something you have to tinker with all the time.

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