pH fluctuating! Help!

[diradiumoxide]

Equipment:
Water pump
Air stones with air pump
Hanna pH and EC meter
~3 gallon tub
200 watt CFL

I'm on a seedling stage, so it's just the water, but I've been trying to keep the pH at 5.8-6.1 and on a day-to-day basis the pH is increasing quite a bit. I keep adding pH down to it to get it back into range, and then by the end of the day (or the next day) it is increasing! The plant can't possibly be doing this as it did it before I even put in the seedling. The temperature of the water is ~79-81 degrees with air temp being 75. The light is on 24/7, is there maybe some stuff growing in the water that is increasing the pH? Can I fix that? I've put aluminum foil over the container with the exception of around the seedling... no idea what to do. Help!

 

[jjames]

hey diradium...

im havin the same problem, i was hoping you got some replies... i was just about to post about my situation as well... i adjust the ph when the lights come on to 5.5-5.7, and a cpl hrs after its back to 6.1-6.5...

i have 3 15 gal tubs, 10 gal in each
air pump and stones in each tub
2 net pots w/ hydroton medium in each tub, 1 plnt in each pot
the plants are still in their cubes so they cldnt be causing this...

400w MH for veg

my water temp is 74-78, air temp is 75 in drk an 82-82 in light, Rh is 40% night an 30% in day ( adding humidifier tho ).

now, when the guy sold me my nutes, he said adding the veg mix of four diffrnt bttles wld bring the ph to 5.5-5.6, but i dont trust that so i got a dig. ph meter... HOWEVER, they didnt have the calbrtng solution, so i used it outta the box, thnikin foolishly factory calbrate wld be good...

does anyone think that the nutes could be bringing my ph to 5.5 for real, but my meter is off and reading 6.1?? and i keep adding ph 'down', actually bringing it to say 4.9-4.0?

can i calibrate my meter to something that i already have? say calibrate it to the ph lvl of my bottle of ph'down'?

wow... pls help anyone!!!

THANKYOU in advance!!

 

[Caregivers]

Equipment:
Water pump
Air stones with air pump
Hanna pH and EC meter
~3 gallon tub
200 watt CFL

I'm on a seedling stage, so it's just the water, but I've been trying to keep the pH at 5.8-6.1 and on a day-to-day basis the pH is increasing quite a bit. I keep adding pH down to it to get it back into range, and then by the end of the day (or the next day) it is increasing! The plant can't possibly be doing this as it did it before I even put in the seedling. The temperature of the water is ~79-81 degrees with air temp being 75. The light is on 24/7, is there maybe some stuff growing in the water that is increasing the pH? Can I fix that? I've put aluminum foil over the container with the exception of around the seedling... no idea what to do. Help!

Hello,

From the little information you have provided, I have to say your water tempature is a little too high. I try to keep my water under 70 degrees. If the water is warm, then algae will start to grow in the tank. Algae causes the PH to climb. Try bringing down your water tempature and see if the PH stablizes.

CGs

 

[diradiumoxide]

I need ways to cool it, then, I'm using a stealth grow box and have no idea how to get it any cooler, it's packed.

 

[GodSpeed]

A/C unit will always do the trick!

 

[Maer]

pics would help too. evaporation is very effective at cooling. how much water is in there?

 

[drofosho]

Well to help find the root of the problem few more questions... How long had the new water been in the res? First couple days of fresh water ur going to get spikes say from 5.8 - say 6.3. next us your temp/ climate consistently 75 degrees night and day even with the light on 24/7 temp changes are another cause for Ph fluctuation especially given the size of your res is on the smaller side. And lastly do u see anything growing in the res? If so, full res change and sum scrubbing.. Sorry to ramble and for the bad spelling, my fat fingers and the iPhone just don't make a good pair lol

 

[420child]

I've found personally that increasing my res tank helped alot to stabilize my PH. Smaller tanks seem to fluctuate more. Nutes will drop you PH so therefor always add nutes than adjust PH. PH will need some time to stabilize so try changing water when in dark cycle so u have some time to check over few hours, or better yet have a 2nd res tank premixed ahead of time so it's ready to go when needed. Also make sure your changing your tank al least every 7-10 days. One more thing I've found to help is using a 2 part nute solution. A AND B type, I had nothing but problems with an all in one type.

 

[this guy]

Your hanna meter out of the box will not be calibrated. Make sure you get the correct calibrating and storage solution. Depending on your meter, you may need 1 or 2 ph cal bottles, 1 for 7ph and the other for 4ph. You will also need ppm calibration, and a storage solution.

Not sure if I understand you correctly, but you say you're having problems ph'ing plain water? Plain water has no buffering properties, and naturally wants to be around 7ph. When trying to maintain ph water, I add 1 tbsp (per 2.5gl h20) of "Big Bloom"; I'm not to sure of what nutes you'll be using, I use foxfarm. The big bloom is such a small amount, but is used as a buffer for when I need to use ph down.

Brings me to another point. You listed air stones, air pumps and buckets; so I'll assume you're running a DWC system, like me. I keep my ph @ 5.1 - 5.8. In order to maintain those ph numbers, I check ppm and ph every 3 days, then adjust accordingly.

Foxfarm nutes will bring your ph down to around 4.5pm, but will gradually raise over time. Only a drop or 2 of ph up will bring it to 5.1-5.2.

 

[HydroManster]

If it is tap water, it will have calcium and magnesium (among other things) both of which will affect the "hardness" of the water. These elements and others also affect the PH as well.

If you do not have bacteria or fungi or algae growing as mentioned that will change the PH, then what you have to do is keep adding PH down to your tap water VERY slowly until you reach or reduce the "buffer capacity" in the water. Once you reach that level the PH will stay where you put it instead of rising back to what it was originally out of the faucet.

In other words, the elements in the tap water want to hold the water at whatever the PH level is straight out of the faucet. These "buffers" hold the water stable at a certain PH depending on the amounts of concentration and other factors. You have to keep adding PH down until you reach this buffer level, otherwise the tap will just rise back up to what it was (the ph level) out of the faucet.

Sometimes the tap water is so hard that you have to add to much PH down to get it stable and this will sometimes unbalance your solution and make it not really useable.

At this point you need to get a RO filter to filter out the hardness.

A water analysis is extremely helpful if your planning on using tap water for growing. You need to know the hardness level and more importantly you need to know how much calcium and magnesium is in the water. This information will be needed so you know how much of these two elements you need to add and will help to form your feeding schedule and how strong you mix your nutrients.

What is the EC or PPM of your tap water out of the faucet and what is the PH level?

Cheers!

 

[Kush Killer]

Your hanna meter out of the box will not be calibrated. Make sure you get the correct calibrating and storage solution. Depending on your meter, you may need 1 or 2 ph cal bottles, 1 for 7ph and the other for 4ph. You will also need ppm calibration, and a storage solution.

Not sure if I understand you correctly, but you say you're having problems ph'ing plain water? Plain water has no buffering properties, and naturally wants to be around 7ph. When trying to maintain ph water, I add 1 tbsp (per 2.5gl h20) of "Big Bloom"; I'm not to sure of what nutes you'll be using, I use foxfarm. The big bloom is such a small amount, but is used as a buffer for when I need to use ph down.

Brings me to another point. You listed air stones, air pumps and buckets; so I'll assume you're running a DWC system, like me. I keep my ph @ 5.1 - 5.8. In order to maintain those ph numbers, I check ppm and ph every 3 days, then adjust accordingly.

Foxfarm nutes will bring your ph down to around 4.5pm, but will gradually raise over time. Only a drop or 2 of ph up will bring it to 5.1-5.2.

damn! i check mine 3 time a day 7am, noon and 7pm everytime i check it its anywhere from 6.5-7.2 ph down to bqck down to 5.2 and next timei check its back up, im using 10 gal res, dwc with a drip system, humboldt nutrients, 100% r/o water (with cal mag asdded) as well as dark energy, super nova, ST and rapid roots.. rh stay 58-65% day time temps are mid 70's to max of 83 and nite time low of 68 on averge 72... im completely baffled.. res is spotless as (no alge or gunk) 4 plants all are about 5 weeks old from seed cracking, but only about 1-2" tall under 400mh.. about 8-9 inchs from canopy idk if thats cause very short nod length or what but again im baffled this my first grow