SHOP PRODUCTS
Houzz Logo Print
dyjohnny

New to hydro, nutrient issues i think

dyjohnny
14 years ago

Hello everyone,

New to this forum and hydroponics.

here's my situation.

I'm trying to grow a type of lettuce called "lolla rossa" as my first hydroponic crop.

This is my "second" attempt before trying to get some answers on this forum.

I'm using a raft system.

Basically i have a 9 liter container 30x35 cm, an air pump with air curtain attached. The air pump is designed for up to 57L containers.

For nutrients I am a bit limited as hydroponics is a non existing market where i live in Romania.

My plan is to use commercial nutrients for soil plants, and mix them and dose them in such a way that I can get acceptable nutrients in the end.

I am using a combination of these 2 nutrients:

nutrient A

http://www.vitaflora.hu/images/osszetetel-vc.jpg

and

nutrient B

http://www.vitaflora.hu/images/osszetetel-V2-09-04.jpg

As I can tell they contain a number of macro and micro elements, but they lack other elements like Ca, Mg and S.

I am using

2.11 the indicated dosage of A

and

0.58 the indicated dosage of B

This gives me in the end, at least on paper an NPK of 18-7-21 [actual elements not K20 or N03)

Here's my process:

Germination - I started the seeds [they are standard seeds, if that means anything to anyone] in a germination box, like a tupperware container. The seeds are placed in small cups filled with LECA, cooconut yarn, and very diluted soil plant nutrient.

The germination results were excellent IMO, i got 25/27 seeds to germinate in less than 1 week they had already cotyledons.

After 1 week I put the seedlings in half strength nutrient solution, explained above. They had started to grow quite nicely, They had their first true leaf. At this time i did not have a pH meter or EC meter. I used tap water to make the solution. I tested the tap water afterward it showed 0.3mS EC and 7.2pH. So i can say i was quite happy that the seedlings had grown in such high pH water. I also moved the container with the seedlings under a south facing window, they had been on the north side of the house until now since I was colder there during germination, and I figured if they had more sun they would grow better.

1 Week later I transplanted the seedlings to the 9L container, the actual hydroponic system. By this time I had a pH meter and EC meter.

I made the nutrient solution with half tap water [7.2] and half demineralized water [ph 6] and the nutrient formulation from above.

I reduced the pH of the water to 5.9 using 9 deg vinegar, about 13ml for the 9Liters. The EC of the solution was 1.2mS. The ambient temperature was around 20-25 degrees.

After the transplant to the raft system, i placed the system under the south facing window, and, in 3-4 days the plants started to show signs of weakness i would call it.

The stem of the leaves has a red/purple tint to it. Some leaves have tipburn. They also seem to have stopped growing, none of them have more than 2 true leaves, and those are kind of as big as the cotyledons [1cm wide by 2-3cm long]

The nutrient water also smells funny.

Can anyone point me in the right direction as to what I did wrong and how could I address the following issues, that I think are the problem with what I did.

I have these hypotheses, please feel free to shot them down, I'm new at this, and I'm still guessing in the dark.

1. The nutrient solution was not balanced. I mean it lacks Calcium and Magnesium. I calculated I'm missing about 120ppm Ca and 44ppm Mg for the 18-7-21 formula. Any ideas how to add these 2 elements? Epsom salts and some Calcium carbonate? Could it be unbalanced somehow because it is not "hydroponic nutrient". Is there any way I can get this to work using soil plant nutrients [not organic] and some other additives?

2. I transplanted the seedlings too soon. in retrospect, perhaps I should have waited 1 more week to do it?

3. The air pump is somehow pumping too much air into the system, perhaps encouraging microorganism growth in the nutrient?

Thanks for reading and feedback

Comments (2)

Sponsored
Closet America
Average rating: 4.8 out of 5 stars133 Reviews
Northern Virginia, Baltimore & DC Metro's Closet Organization Company