why does the ph in my NFT keep changing to alkaline

[G_Starr]

Hi there ppl,
i am in the flowering stage of my grow but recently the contents of my resevior keep changing to give a alkaline reading, when i have cleary put in a solution of neutral ph in i am puzzled as to why this is and need to find a solution pronto
any help is appreciated

cheers!

 

[bombadil.360]

do you see the plants being affected by it?

if not, maybe the instrument with which you measure your pH is not calibrated or is faulty.

?

peace

 

[Scrogerman]

Sounds quite possibly that you need to raise your feed/EC, its about half way through 12/12 that the plants are gonna want more/the most food. A sharp upward daily drift in PH surly indicates this, What strength feed/EC are you on now? & what nutes are you using? & how are you testing your PH?, with a litmas or dripper/colour test by the sounds of it??? Let us know n we'll help you out man. At least the PH is going up which is a good sign & this should be easily rectified. Lets us know man!
Oh i re-read your post, PH Neutral = PH7, way to high anyway man, NFT & Rockwool you wanna adjust the PH to 5.5-6.0, Neutral(7) is way to high man!

 

[Mr. Greengenes]

Welcome to ICMAG, G starr! The minerals in naturally hard water buffer against low PH. Acids can lower the PH temporarily, only to have it bounce back up as the minerals reassert themselves. Not sure what your water is like, but it sounds hard, and if so that would explain it. The hardness is usually caused by some blend of dissolved limestone and epsom salts, which you might notice are plant nutrients. Not altogether a bad thing other than they throw off your PPM calculations and nutrient blend requirements until you learn to adjust. bombadil.360 rightly points out that if they look ok, they are.

 

[Scrogerman]

Welcome to ICMAG, G starr! The minerals in naturally hard water buffer against low PH. Acids can lower the PH temporarily, only to have it bounce back up as the minerals reassert themselves. Not sure what your water is like, but it sounds hard, and if so that would explain it. The hardness is usually caused by some blend of dissolved limestone and epsom salts, which you might notice are plant nutrients. Not altogether a bad thing other than they throw off your PPM calculations and nutrient blend requirements until you learn to adjust. bombadil.360 rightly points out that if they look ok, they are.

So you dont agree with anything i said brotha Green?
After a few days of adding PH Down(Phosphoric), the waters buffering capacity should be achieved anyway, like a sponge, it has a saturation point & should stabilise, if,the ppms are in the correct range. If the PH keeps rising, then surly this indicates that ppms need to be increased, Hard water has better buffering capacity than soft water anyway & is much more PH stable, Less PH down should be required in Hard water, Ive worked with Both Hard & Soft water. My money goes on weak ppms bro! Brotha Green has some valid points!
Is your water Hard or Soft?
Are you using Hard or Soft Water Nutes?
What Are your ppms?
Can we have some pics bro?

The OP, G-Star, points out that this is only started happening recently & hes in Bloom, this is why i came to my original conclusion. I have done alot of NFT.

 

[G_Starr]

thanks for ur replys ppl!!!
yeah i am using a liquid ph test kit unfortunatly thats all i have available right now the solution i have been putting in is around 6ish i guess given the color, yeah the plants have been affected badly by this i have just come back off holiday from morocco to find this problem. usually i dont have many probs with my nft but 2 of my recent grows have been affected by this predicement,
the roots have gone a bit soft aswell so im trying to dry them out a bit and check the state of them, i have 4 killing fields in the affected system and the symptoms r that the flowering tops have started to crisp at the top and work its way down leaving few leaves.i have 4 in the system and 2 r badly affected i really want to keep the purple pheno. i shall try and get a pic on here by end of day !

ThankQ for all ur help
its much appreciated
G_Starr

 

[G_Starr]

am using canna flores btw

 

[G_Starr]

these are the best pics i can get atm will take some at lights off aswell

 

[G_Starr]

its hard water aswell forgive me for my multiple posts im reall high on budder lol

 

[ChaosCatalunya]

Hi there ppl,
i am in the flowering stage of my grow but recently the contents of my resevior keep changing to give a alkaline reading, when i have cleary put in a solution of neutral ph in i am puzzled as to why this is and need to find a solution pronto
any help is appreciated

cheers!

By "keep changing" do you mean daily ? That is normal, you [daily] check the EC and pH, and adjust both. In a Hard Water area this means adding pH- daily. Optimum [Nutrients] from Growth Technology has the best buffering action I found, meaning less work adjusting and more stability.

Are you really stirring it properly before setting or checking the pH ?

Are you using any dodgy materials in the solution ? e.g. PVC Garden hoses, metal, or just plain dirt ?

Are you aerating the solution too much ? This can cause the pH to rise

Are you checking the solution daily ? Who was doing it when you were in Morocco ?

NFT is a knife edge, great when going well, but a fast trip to shitsville if it goes tits up....

If you have to leave it alone for over a day, it is probably not the best system for you, NFT needs constant attention, ignore lazy people who tell you "you can get away with x"... Active Systems need active input to achieve their potential advantage. I grew NFT for years, then switched to COCO as it is so much easier, forgiving and flexible.

The test kits [white bottle from Nutriculture ?] work fine and do not give false readings like unadjusted pH meters... it is just a bit more fiddly.

 

[G_Starr]

im using a regular small nft with no foriegn objects in it, i shake the solution in a big container vigorously before adding to the system and also check ph before adding.
no added aeration,no i havnt been checking it daily and i mixed up a lot of nutrient solution for my freind to add while i was away but i guess the ph changed in the meantime.
and yes the nutriculture ph liquid test is what im using

should i be adding a small amount of freshly mixed nutrient solution daily as opposed to a bulk amount for 3-4days?

thankQ very much for ur help
G_Starr

 

[Scrogerman]

Hey Chaos,
Great advise man, Ive never heard Aeriating a solution too much will raise PH Before, Ive run DWC with 40ltrs per min through a 70ltr Res with absolutly no effect on PH whatsoever, just for the record, I know Runnig Co2 through a solution will raise it though, Mmmm.

those plants look badly locked up man, probably due to PH problems & Salt accumilation in the RW, As Chaos stated NFT needs Daily PH adjusting, especially untill the solution has stabilised, usually 2-3 days after a change out, If PH still raises say .3-.6 then like i said before your feed strength needs to be raised. Rockwool needs to be flushed every fortnight, Minimum, Weekly is best in NFT, Unwanted salts will build up in the medium(RW) & they need to be flushed out, a fault of/with Rockwool growing, it accumilates Salts & they need removing or it has the same effect as you seem to be having there in your Grow. First thing i would do now is flush the hell out of the RW before your next change out, Weak 1/8th strength solution(EC0.2) for the flushing PH 5.5. EC wants to be around 1.0 in your Res after the Flush, if your 3-4 weeks into bloom, but thats strain specific, & some strains will need anything upto EC2, it all depends, Watch PH, if it continues to Raise after 3 or 4 days, its certain that your nute strength needs to be increased! Good Luck Man! Like i said ive done alot of NFT growing man!

 

[G_Starr]

ThankQ Scrogerman and ChaosCatalunya i will be putting this into effect immediately, have u got any advise for how to flush my rockwool? shall i keep watering the cubes with ph adjusted water? and flush the system with the same adjusted water that conatins no nutrients ?

 

[Scrogerman]

This was my last NFT grow, it was mostly very successfull, shame the Quality of genetics wasnt up to much!



Good Luck man!

 

[Scrogerman]

ThankQ Scrogerman and ChaosCatalunya i will be putting this into effect immediately, have u got any advise for how to flush my rockwool? shall i keep watering the cubes with ph adjusted water? and flush the system with the same adjusted water that conatins no nutrients ?

No, If you use a very weak solution, say 1/10th or 1/8th strength solution its much more effective than using plain ph'd water. The elements in solution are like a magnet & draw out the accumilated salts much better than just plain ol water, go for 1/10th strength, very weak, & remember this practice of flushing RW must be done every week to fortnight. You want to use at least twice x2 the amount of flush solution to the volume of your cubes!
Oh & use a lower PH, 5.5 man! Ionic is great, i love the stuff in NFT, switch to bloom ferts after 3 weeks though, no matter what, the Grow at 3-1-3 is a little weak imo! Mates of mine just use the Bloom formula from wk 1 to wk 10+ with great effect! Sorry you said Canna, same crack, better nutes!
Like Chaos said Optimum is very good,-Old Faithfull!

 

[G_Starr]

yeah thats wicked scrog bro! what were ur genetics for that ? im growing herijuana killling fields ko kush and trainwreck, i have also just finished a full moon (nirvana) grow which was very satisfactory and made killer hash and oils

i have been growing for about 12yrs with various methods mostly nft and outdoor, seems like since i moved into my new place ive had allsorts of new probs to face :-( its been kinda difficult lately to recapture the quality of my previous grows.

but ill always be growing so there is always room for improvement and new education hehe

cheers

 

[Scrogerman]

I Like to use a 100ml syringe for flushing cubes or sometimes i use a pump in a bucket, with a hose attatched via clip, set on low! both ways will work! Good Luck Bro!
Always flush RW bro!

Last was 'The Ultimate' from Dutch Pssion, its Shit imo! In that Pic i posted, easy to grow, its just Shit! lol! Never again will they get any of my money!

 

[ItsAllOver]

Sorry if I am repetitive, I haven't read thru the thread...
- Do you clean with bleach? If so, you might not be rinsing thoroughly. I had this problem once, but it was in DWC.
- Are you using new hoses? I have found a particular manufacturer of tubing that seems to have some sort of powder or otherwise alkaline substance on their shit that must be rinsed off else cause havoc on pH and makes my skin break out...

 

[G_Starr]

no i dont clean with bleach,i use a anti-bac cleaner before each grow. i have a 100ml syringe so i will repeatedly flush the cubes using that

 

[Scrogerman]

Thats the Hammer bruv!