Can't get ph down

[Herb Johnson]

Hi guys,

​​I have just flushed my plants and I can't get the pH lower than 6.2. I'm growing in 20 L pots with coco. I firstly maxed up 60 L of weak base nut and house and garden drip cleaner at 0.5 ec and pH 5.5 I flushed until first run off and collected 20ml to check the ec and pH then continued to put the rest of the 60 L's through and then collected another 20 ml of the final run off water to check. The first sample taken had a ec 1.7 and pH of 6.6 the final sample had an ec of 0.7 and a pH of 6.2, still a long way away from a pH equal to the water going in, so I mixed up another 60 L. I'll make the rest quick. Put the 60L through followed the same process of sampling. Final ec 0.5 ( perfect) pH 6.2 (wtf).

6 times the volume of the pot went through to bring the pH down by .4, I'm confused.... I wanted to get the coco down to at least 5.8 as I'm only in week 3 of flowering and ideally I'd like to finish at about 6.4 but if I can't get it down any further it will finish at around 7.

Confused and in need of some advice

Herb.

Sorry if this is in the wrong place or there is already a thread on this subject. I looked around for a while and couldn't find a relivent post.

[Herb Johnson]

An answer for my own question.

I had a slight calcium deficiency and I treated it with trace elements. Calcium is a natural ph buffer it will stabilize at a pH of 7. So I thought that after treating my plants there may have been an excess of calcium that is dragging my pH up.

Just a thought because,

I use shell grit in my aquaponics system to maintain a pH of 7. Beneficial bacteria thrives at a pH of 7 and aquaponics is using fish waste to feed my plants. The bacteria converts the ammonia to nitrites then to nitrates so the plants can feed.

[gicker]

Hi, do not get to hung up on the ph,i am in soil and my ph is about 6/7-7 my water ph is 5,6 got old led pipes.

[Dust]

hi man don't know why i miseed this i'm pretty sure i had written something but must have not been till the end

Could you post a pic of your plant please? seeing her will for sure give us a little insight on what could be happening Or not but at least we will have it

after your big flush it would have been nice to test the runoff water again a few days later to see how things were evolving in the medium. did you check it since?

Good luck

[#Robbo#420#]

I believe freshly squeezed orange Lemmon juice works not in hydroponics go's off haha works for coco what do people think

tastes better as well defo all organic

as iitsays flush till runoff is correct then should be ok why do people flush during flowering should not let nutes build up for flowering get bigger buds

[leyus]

Get your coco mix in 1:5 ratio with distilled water, shake it in bottle and check ph of that. This will give u true medium ph. Run off in coco is good to check ec but ph is meaningless from it due to coco nature. It's not like in soil unfortunately. 

[Snake]

I know this is an old topic but flush your plants with water that is 5.5 ph and continue until you get a reading of your waste water or run off of 0.4 ec on your nutrient tester but next time buy your soil that has been or got a fixed ph level to start with. I hope this helps