Understanding Ppm Levels Of My Water

[Sid Taylor]

Hey all. Just started a bubblegum grow last Suday. Got a Quick Dip TDS meter yesterday. When I got home I tested my nute tank solution and got a reading of 1600. I tested the nutes coming back into the nute tank from my 12 buckets and it was between 300-400. Temp is around 68 F all the time. Out of curiosity I measeured the unsoftened water I use for the nute tank and got a reading of 1100.

 

I have a sump pump hole that is close to my room and it runs constantly. The big "O" that runs around the footing is tied into the sump pump hole. There is a spring in our back yard that runs 10 months a year and some of that water must get into our sump pump hole as when the spring dries up so does the sump pump hole. Anyways, I tested that water and it read 300 PPM. I tested the ph of it as well and it read around 6.

 

So my question is what PPM should my water be before I add nutes and ph down? I think I understand that I increase this level by 200-300 PPM for early veg.

 

Thanks to all that can help.

 

Cheers!

 

Sid

[F420]

Congats on your grow, thats a mighty fine strain you have there.

 

So my question is what PPM should my water be before I add nutes and ph down? I think I understand that I increase this level by 200-300 PPM for early veg.

before you add anything your IDEAL ppm of plain water is 0 but thats not obtainable in reality, unless you are using R/O water.

For instance my water usually always measures around 4 CF which is roughly equal to 140ppm.

In my case I dont bother measuring it before I just make sure that it doesnt go over 900ppm veg and 1600 flowering. But I have seen many cases of people running higher nutes without problems.

Now that doesnt mean what I do is right, but I just do what I know works for me.

The amount of nutes the plant can eat depends on so many factors including the strain. and your strain I have never grown.

Heres a bit of reading for you, I done a quick search on aussie sites and found this guide.

Now it from a hydroshop up in Qld somewhere, so im not sure as to the reliability.

ph is ideal between 5.5 and 6.3.

 

 

 

Nutrient Strength is CF or EC and depends on many things

 

More air flow= more strength or you get stretching

 

More humidity= less strength because the transpiration rate is slower (For Transpiration read evaporation from leaves)

 

More temperature=less strength as the nutrients are not used at same rate as water in solution and nutrients will rise in strength causing over fertilisation / tip burn

 

Plants using more water because it is hotter or the humidity is drier and the nutrients are left behind affect the rate of mineral salt build up in media. Perlite or Rockwool or anything that can hold onto nutrients might have a nutrient salt build-up. If we flush it clean regularly then use normal to slightly weaker (CF=-2; EC=-0.2) or maybe use -6CF to -8CF and not flush. Depends on the level or build up. Are you a good grower and can tell or not? Symptoms often sluggish growth and leaf shape curled (Note: beginners should know these are symptoms of many things, and you need to have eliminated a lot of these other things first) If you can see this happening before tip burn gives it away then you know the flushing or reduction in nutrient strength is needed.

 

So where do I start. In free flowing NFT, Clay type systems where build up is low, Seedlings at 8-10CF (0.8 to 1.0EC) and grow at 18-24 CF. Stay there until flowering aggressively developing plants will take up to 24CF to 28 CF. The stronger you go the better flowering, sturdier stems and branches, heavier fruiting plants should be. Drawback is the weaker you go the faster the plants grow, the longer the distance between branches/nodes, the leafier, taller the plants will be. Flush (0CF to 8CF) plants for 2 days before harvest to remove excess fertiliser for taste. High CF grown plants could add a day of flushing. If flushing causes CF to rise then dump tank and restart. E.g. you flush with tap water at 2CF, come back in 5 hours and its 8CF, next 24 hours still 8-10CF. The flushing is no longer working. Use plain water again at 2CF, and it rises to 8CF again in a few hours. Best to flush and dump, flush and dump. (If you can do that every week or two see your crop go CRAZY!!!! Highly recommended. Better effect than superthrive or Nutriboost!

As for new plants, I often run no nutrients or up to 8Cf while introducing them - but sometimes I just don't worry too much, and give them a flush with water so their pot/root area gets a low dose of nutrient solutions.

 

Hope all that helps you

 

 

 

PPM explained

is a website that explains it all,

Edited March 20, 2004 by Ferenge420