PPM question

skunkushybrid

skunkushybrid

New Member
supdro said:
I am trying to remember where but I read that nutes should only be at 1/4 to 1/3 strength. is that false? if so what should it be? also as a newbie what should be the first thing to buy a ph or ppm meter to regulate for hydro solution? I have already had nute burn on my plant. I didn't know that it could cause stunted growth. I had too much the plant started to turn yellow on the ends and no growth. changed the solution and it is bushy as heck but still stubby. will it get taller soon??
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For hydro' you'll need both.

1/4-1/3rd strength is false yes. You cannot possibly know the ec/ppm by feeding lower strength nutes.

I really can't see how NPK nutes will read different EC (electrical conductivity) levels.

I believe superthrive is a product that messes with ec a little, but I've never heard this about normal nutes.
 
M

mrfake

Active Member
I can't speak for GH, but I started with Vita-Grow AB (dry nutes in RO water) at 350 ppm for seedlings, then stepped it up to +-1000 towards the end of veg. Now, 4 weeks in flower I'm running advance sensibloom AB with bigbud/tarantula at around 1900ppm and the ladies are rocking out with no burn. I kept stepping up and thought that was too high, but after asking here and watching for burn there's no problems. I'm also running co2 and have a climate controller so that probably helps mucho. My advice is go with 1/2 of what it says and work up over a couple weeks, if you START seeing a problem feed with plain water once and back down a hair. I've been involved in making growrooms and helping with soil grows but this is my first hydro, its a quick learning curve but you learn a lot (or kill your plants).


 
skunkushybrid

skunkushybrid

New Member
I'm confused...


I can see nute burn. Only slight at the moment, or at least from the evidence in the pic's, but i imagine this could get worse if you don't pull back on the concentrations.

Doubtless the CO2 is preventing things from being any worse.
 
M

mrfake

Active Member
yeah, the edges have had that tinge of yellow for a while. When the rez drops a little I'll just top it up with just RO water to bring it closer to 1400-1500. Some of that ppm (100-150 I think) is just the tarantula which should be pretty much inert as far as causing burn. These things are also big (well over 5 ft) so I think that also helps them cope.
 
skunkushybrid

skunkushybrid

New Member
I use every AN product except tarantula and humic acid. i use Sensi A n B for the base nutes.

tarantula seems very similar to piranha to me, but i like the mychorrizal fungi in the piranha.

The piranha cost me around £25.00 ($49.00)... I haven't checked on the price for tarantula, how much is it?
 
M

mrfake

Active Member
I think I paid $45 for it. I wish I had a control to see if it made a serious difference but the way I look at is if it made another 1/8th ounce over 3 plants it was worth it.
 
skunkushybrid

skunkushybrid

New Member
mrfake said:
I think I paid $45 for it. I wish I had a control to see if it made a serious difference but the way I look at is if it made another 1/8th ounce over 3 plants it was worth it.
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Oh it'll definitely be worth it. I kinda almost tossed a coin to decide on tarantula or piranha.

Piranha just edged it for me because of the mychorrizal.
 
jbreeze

jbreeze

Well-Known Member
pandabear said:
i use the hanna meters and it took me so f'in long to find this info, but if you are using hanna PPM meters they say 900 ppm would equal 1.8 EC


just double your ppms and put a decimal in it to find out ppm to Ec conversion

greenhouse seeds has a video about growing thier ww plants. the highest they ever used for that plant was 1.9 ec so i been using around 900 ppm on mine just to be on the safe side which is 1.8 ec

my big bud plants could take like 1100 - 1200 ppm which is like an ec of 2.2

here is an easy way to find out if u are using too little or too much ppms for your plants. first you put the water in your res (this is only for hydro) then u nute it to say 900 ppm, come back the next day. if the water has gone down like 2 inches it means the plants drank 2 inches of water. if the ppm is still 900 after they drank the water, it means the plants are drinking the same amount of water as they are the nutes and you have found thier optimal feeding range for that time in thier lives

now if they drank 2 inches of water and the ppm went down to like 700 then you know the plants are drinkin more nutes than water and you need to add some.

if the ppm is higher after they drink water it means they need less nutes and are trying to extract just watter and leaving behind the nutes, and you better fix it before they begin to burn
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Very very nice..makes much sense..priceless
 
Earl

Earl

Well-Known Member
If you check Dutch Master web site,
DM recommends you use a max 70% nute load,
unless you start with 000ppm water.

Even my RO machine doesn't make oooppm water.
It takes a very expensive commercial RO machine to do that.

If you read Lucas,
as in Lucas Formula,
and Pure Blend Pro,
He recommends 50% nute loads unless,
•you have 000ppm water,
•you have Co2
•you have High Intensity Lighting of 1000w

If you can meet all those conditions,
you can benefit from 100% nute loads.

If you have tapwater.
Floros,
and no enhanced Co2,
then you should use lower nute loads accordingly.




.
 
M

mrfake

Active Member
oh, skunk.. I saw a show the other day on the evolution of plants and the role of mycorrhizal fungi. (For those who don't know, they increase the surface area of the root and help the plant leech out nutrients faster and more thouroghly.. while they live on some sugars from the plant) Definitely going with piranha next time.

And I'd go more with the 50% rule than go off of ppm, nute companies probably have different "base-lines" that you should take into consideration.
 
email468

email468

Well-Known Member
oh gotcha! i use the manufacturer recommended dosage as a guideline - i use PPM as the deciding factor. so if the nutes recommend 1/2 dosage and i use 1/2 dosage but my PPM is over 600, i'm going to reduce the dose until my PPM reads 300 (or whatever I am shooting for).
 
tsnow

tsnow

Active Member
Great Thread...

Heres some useful information I found a while back.
PPM Conversion Factors

Not all TDS meters will give the same PPM reading. The main reason for this is that different meters will use different conversion factors. These conversion factors are based off the EC reading. For example: A meter that uses a conversion factor of 0.5 will display a reading of 0.5 times that of the EC reading. If the EC reading is 1000 µS then the ppm reading will be 500 ppm. It is as simple as multiplying 1000 by the conversion factor of 0.5. If the meter uses a conversion factor of 0.7 (the most common conversion factor used) then 1000 µS would be 700 ppm (1000 x 0.7). When purchasing a TDS meter it is very important to find out what the correct conversion factor is for the meter. It could make a difference of more than 200 ppm! Not only is it important to know what the conversion factor for the meter is, it is also important to know the conversion factor of the calibration solution. Generally speaking, Genesis calibration solutions are for meters that use a 0.7 conversion factor and the Hanna solutions are for meters with a 0.5 conversion factor.
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A 1000 µS is the same as 1.0 mS. Heres a link to more info on it.
TDS and pH Explained | BGHydro
 
moon47usaco

moon47usaco

Well-Known Member
But all you are talking about high ppm readings being XXX or XXXX but how does that relate to weather you are using RO (0 ppm) water or you are starting off with a high ppm reading from your tap water... ??

If say, for readability and clarity with my question, the magic number 1000 is high or the max ppm you want...
Is that high from 0 RO water or what... ??

If you are using the same nutrient solution strength but you start off with 250-500 ppm tap tap water does that mean that same HIGH ppm would be 1250-1500... Or if you start off with high tds water are you limiting yourself and 1000 is the magic number weather you start off with 0 or 500 ppm water... ??

I am not sure i made that completely clear... ??

Answers, Questions... ??
 
email468

email468

Well-Known Member
moon47usaco said:
But all you are talking about high ppm readings being XXX or XXXX but how does that relate to weather you are using RO (0 ppm) water or you are starting off with a high ppm reading from your tap water... ??

If say, for readability and clarity with my question, the magic number 1000 is high or the max ppm you want...
Is that high from 0 RO water or what... ??

If you are using the same nutrient solution strength but you start off with 250-500 ppm tap tap water does that mean that same HIGH ppm would be 1250-1500... Or if you start off with high tds water are you limiting yourself and 1000 is the magic number weather you start off with 0 or 500 ppm water... ??

I am not sure i made that completely clear... ??

Answers, Questions... ??
Click to expand...
The PPM should be measured AFTER adding nutes to tap water. So i you are shooting for a PPM of 300 and your tap water is 250 then need only add 50 PPM worth of nutes to bring the total up to 300. Does this answer your questions?

Also note - you should only use 50% nute loads (according to Earl who I trust knows what he's talking about) if using tap water. so if the manufacturer is saying 600 PPM - you should be shooting for 300 PPM
 
moon47usaco

moon47usaco

Well-Known Member
So by using RO water you greatly increase the amount of nuts you can add to your water... There fore greatly increasing your control over what minerals are available to your plants...

In your scenario if you are only adding 50 ppm of nuts to a 250 ppm water base then you are only allowed a 16.6% control level... 16.6% nuts the rest is who knows what... You could have an unbelievably high magnesium content in your water for all you know...

Luckily your local city is required to report annual average/max tds levels and break down what chemicals make up those tds levels...

Email this would be a good idea in your case... =]

I will find a link that will help you gather this info... =]

Thanks for the clarification... =]
 
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