PPM and PH going up and down need some advice

So Im currently in late flower and my ppm and ph seam to be on a roller coaster.... Im growing two white widow strains under a 400W in a 4x4x6.5 tent..... I dont understand why the water is so unconsistant. I am using GH as my nutes and PH down powder form from GH.... Im currenly 6.2 ph and 2083 ppm my plants dont like it and in a given day the ph will change by +- 1.5 They still look pretty and getting big as well...My system is a RDWC so im not really a noob.... and they set in a 15 gallon container. Thanks for the help.

Note: No root slime.... a little white build up on containers.

Cheeto720 said:

So Im currently in late flower and my ppm and ph seam to be on a roller coaster.... Im growing two white widow strains under a 400W in a 4x4x6.5 tent..... I dont understand why the water is so unconsistant. I am using GH as my nutes and PH down powder form from GH.... Im currenly 6.2 ph and 2083 ppm my plants dont like it and in a given day the ph will change by +- 1.5 They still look pretty and getting big as well...My system is a RDWC so im not really a noob.... and they set in a 15 gallon container. Thanks for the help.

Note: No root slime.... a little white build up on containers.

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why so high on the ppms

Drop your PPM's and PH down.

I am trying to drop my ppm and my ph down but my problem Im facing is that i add 5 gallons of tap water ( I know may be a problem), then i gradually add ph down and top up to around 1100 ppm dont even know this to be 100% right. Really need the help as you can read lol

I add so much water because the two girls i have are big and still need time.... I can see defeciencies in them and trying to prevent this in the future.

With hydro you're trying to find the sweetspot whereby NUTES and wTer are taken up at the same rate leaving the return solution near the same as when it left the res.

Ph should be allowed to drift between 5.2-6.2 to get full access to the nutes at their optimum uptake levels.

If you're setting your ppm at 1100ppm and then adding pH down it too will increase your ppm's.

If you're sending your NUTE solution out to feed at 1100ppms and its returning more than 150ppm higher than it was set to then you're over feeding the ppm's as the plants are up taking the water and leaving a stronger nute mix behind which can't be taken up.

This in turn can cause osmotic pressure change in the roots which can have drastic effects too.

Try to find the sweetspot.


Hint.... The sweetspot changes at each stage of growth and expect nutrient demands to get less the closer you get to harvest.




J