quick ph question

[Stalldaworld]

im about to fill my rez.. ph of tap water here is about 7.2
should i fill rez then adjust with ph down before i add nutes?
or
fill rez and add nutes then add the ph down?
and remeasure ph

i guess im just wondering how much the noots are going to affect ph
thanks

 

[guest]

the nutes will drop your ph.........you may not need to drop ph at all

 

[Wait...What?]

the nutes are going to try very hard to affect the pH. so let them. wait at least 2 hours between mixing and your first pH test.

 

[FreezerBoy]

Are you growing in the res? If so, mix water, nutes and pH down in separate container and then pump/siphon/drain into the res. Mixing directly in the res can cause serious plant burn.

 

[Stalldaworld]

thanks all
tomorrows task: geta better ph meter...
hopefully the noots did it..

24 gal rez....ph tap water 7.2 ppm 100.....
after 30 teaspoons of pbp grow..brought it to 300-400 ppm at the 5x conversion...
rez temp 70, room 73, humidity 65, ph: unknown
12 girls, e&f 2 large home depot mason trays, scrog, 400w veg (hopefully 2 weeks) and moving up to 1k flower
genetics: mandala

 

[FreezerBoy]

Get something to test pH ASAP. It determines what the plant can and cannot absorb. Any aquarium store will have a $5 test kit. You'll probably want some pH Down, too. No idea if the aquarium pH Down is good for hydro. The Hydro store version was cheap enough and a quart will last me for years.

 

[Stalldaworld]

Thanks freezer
I have a cheepo kit but it only measures to 6.0 and it goes by color like a science class. Mix nutes=brown water. Hard to tell what ph is exactly. Ideas? I do have thehydro ph up and down if needed

 

[BENJI]

the nutes are going to try very hard to affect the pH. so let them. wait at least 2 hours between mixing and your first pH test.

Perfect answer....even check your res the next day...

 

[ubet28]

Buy a PH pen. Also i agree with freezer boy mix the water in a separate container. I set my PH to 5.8 if it is swinging up. And 6.3 if its swinging down. I then let it swing .8 before i adjust.

 

[norcalsmoker]

good advise ubet28 ph does seem to swing at first. Strains matter to some eat more water some eat more nutes so start off with one and u might get a surprise a day later if you dont know the strain. Good luck with it and meters are gardeners good friends.

 

[FreezerBoy]

Thanks freezer
I have a cheepo kit but it only measures to 6.0 and it goes by color like a science class. Mix nutes=brown water. Hard to tell what ph is exactly. Ideas? I do have thehydro ph up and down if needed

If your solution is too dark to use a test drop kit, you may be grossly over feeding. Since discovering the "EC and pH move in opposite directions" trick, my solution is near indistinguishable from tap water when viewed in the 0.5 ml test tube.

While the kit stops at 6.0, 6.0 is yellow while 5.5 is YELLOW. You can tell when you cross the line. Never forget that math is your friend. Draw 5 gal of tap and measure pH, add 0.5ml pH down and measure again. Now you know how much movement you get from 0.1 ml in a gal of your water.

My last grow was a Mandala 8 Mile High. Went for 12 weeks in a DWC. Not one EC reading was taken. All nute adjustments were based on pH readings from a test tube kit. It might be different if I had multiple tanks to measure but, with one, I can't imagine putting up with the hassles of a pH pen.

 

[dongle69]

Many nutrients have fulvic/humic acid in them, which makes the water brown, rendering ph drops useless.

 

[FreezerBoy]

That's why I said "may."

 

[Stalldaworld]

yup...running pbp

 

[Hydro-Soil]

rez temp 70

Not good. Need to lower that or find out FB's secret.

humidity 65

Ok for now, dangerously high for flowering (mold/mildew issues)

ph: unknown

Bad


Depending on the calcium levels in your tapwater, you may need some Cal/Mag+, along with that PBP. Wasn't the Lucas ratio with PBP 15ml/PBP and 5ml Cal/Mag+? Not sure now but something you would do well to look up.

 

[Stalldaworld]

thanks hydro...
i was under the impresion that you could get away with a little higher res temp in an E&F...
Res sits on a concrete floor and outside temps are cooling down in my neck of the woods so im keeping my fingers crossed that i can get away with this.

fans will be moving air in flower...dehumid if nec. Crossing that bridge when i get there.

PH: getting a digi pen soon...stuck with aquarium drops for a minute.

Ive been doing alot of reading about pbp...they say calmag is def nec with ro...im using tap which should have some cal in it already. Me being new to the dro, im going to let the ladies tell me what they need instead of trying to prevet a problem that i dont know exists yet. If some cal mag def turns up ill hop on it.
im using 30teaspoons of pbp in my 24 gal res...anyone know how many ml are in a teaspoon?

thanks for commenting hydro. Your a great help around here K+

 

[FreezerBoy]

1 tsp = 5ml

 

[Stalldaworld]

so for rooted clones (mandala) thats a low dose...that doesnt scare me too much.
thoughts...?

 

[Hydro-Soil]

thanks hydro...
i was under the impresion that you could get away with a little higher res temp in an E&F...

Hahahhahahaha.... sorry, missed the part where you said E&F, res temp is fine then


I'd seriously consider looking for a source for RO. Not having to try and 'figure it out' is very good for the nerves and RO does such a great job. Yes, you'd have to pick up some Cal/Mag then but at least you know there are proven recipes for PBP and Cal/Mag that you know work.

Glad you can at least use your tapwater..... the brown slime/snot that grew in 4 days with mine is unbelievable.

 

[Stalldaworld]

ok i so i got a ph pen and promptly measured my ph, which as expected came out to high (6.9) my girls were showing the pain with yellowing leaves and some curling as well....
after the oh shit feeling went away i read the directions on the stealthydro PH down i had and thouht i followed the directions correctly based on the amount of water that was in my res. so i mixed in the down and waited about an hour and took my second reading....(this is when the OH SHIT feeling came back much stronger than before)

my pen said the ph was 3.7...at this point i was having a Bobby Bugout...i almost broke the bowl i had in my hand.. lol (i thought i was going light on the down to see what was going to happen, obv. not the expected result)
so i prolly did a stupid thing and added some ph up which settled the ph at 5.4
im waiting to take another reading to see if things are staying around 5.4

should i have just changed my res out and started from scratch?
very nervous about killing my ladies right now