Nute levels in hydro

[Guest]

Before I ask this question, I'll first say that I spent a good 20 minutes browsing the board to find out for myself, and had no luck

 

I'm a little confused here - being the ametuer botanist I am - when reading about nutrients I see all these terms thrown about ... such as EC, CF, PPM, do they all refer to the same thing? I have a vague idea from somewhere that PPM refers to parts per million .. I think. Looking up nutrient level readers I've noticed they're not exactly cheap either, well into the $100+ mark for most electronic readers.

 

Are these things really necessary and is there a cheaper 'solution'?

 

Hehe oops my bad pun there

 

Thanks

[Guest weekprik]

it depends on your setup, but for hydro not sure about soil the things are worth their weight in gold, i use a truncheon and i was weary about paying $135-00 for a tester but when i got it home it paid for itself that is my nutes were twice the correct limit.

AND my mix was made up by the instructions.

 

 

 

Mate if your growing hydro get a truncheon tomorrow.

 

 

TDS, EC, PPM etc all mean the same thing just a different way of measuring it, my truncheon show EC, PPM etc.

 

Plant nutrient strength is about osmotic pressure, not the actual amount plants eat.

The water usage is greater than nutrient salts so nutrient strength should rise overall.

If adding water still gives a higher reading then some salts have built up in the system/media and you should flush the system with water until the water ppm is close to whatever water is normally in your area.

 

nutrient strengths-

Use more if high airflow, less if high humidity, go stronger if too tall, weaker if too short and so on...

 

So I start with a CF of 10, go to 20-24 for grow and 24-28 for flowering.

in ppm check your calibration solution for comparison. If dividing the ppm on the calibration with the CF of the calibration gives you 65, (or whatever) multiply my CF's by 65 (or whatever)

Edited June 12, 2003 by weekprik

[Guest]

God damn weekprik, that was FAST

 

Thanks for the info ... hrmm $111 at hydroshop for one.

 

These things sound great. Definitely on the list for later on.

 

In the meantime, has anyone got any advice regarding how to get by without one? I've heard that a good technique is to use 1/4 strength of what the instructions on the nute label recommend.

[Guest weekprik]

1/4 for clones and young plants, 1/2 for veg and 3/4 for flowering. too little is far better than too much.