Fox Farm causing pH issues?

@bob31 @Bobbi @Countryboyjvd1971 @Donaldj @peachfuzz and /or anyone else who might be able to offer input
Strain; ILGM Cheese

Soil in pots, FFOF

System type: Vivosun

PH of runoff : struggling to get above 5.0

What is strength of nutrient mix? See below

Indoor : 400 adjustable ballast

Temps; low 80s down to 70 at night

Humidity; 45% to 50%

Ventilation system; Yes, fans

AC : whole house unit

Co2; No

Everything was going great using BigBloom. Then started flower stage on July 1st. So I started adding “bushdoctor kelp me kelp you” and then the pH problems started. I’ve been gradually flushing with clear water, pH at 6.5 to 6.7, for past 2 days. This did raise the ph from 4.2 However, I cannot get the pH to come up past 5.0. Also, my runoff ppm does drop below 800s but then jumping back up into 1800s (overnight) even though I’m using clear water. So my question is this; should I keep Flushing perhaps using 7.0 to 7.2 clear water? Or, should I attempt transfer into fresh soil? She’s lost 50% of her weight and does not seem to be recovering. I’m so bummed, to come so far, to lose so much, so fast. Can you hear the frustration in the background :disappointed:


You should be flushing with Fox Farm Sledgehammer flush . It’s ment to break up salt build up.

When I feed I go in at 6.5 ph
And run off is about 6.5-6.3 ph
I don’t think the kelp is you problem, have you flushed before?

Only flush with clear water. Unable to locate sledgehammer locally and Amazon has one to two month wait.

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Go ahead a order . If your haveing a salt build up fresh water want be enough to break it up.

Oh wow, I just had a lightbulb moment. I’m using tap water because ppm’s run 120 to 130. However, could be my tap water is heavy with something that is compounding the problem? I’m thinking, go with distilled water only for now?

Yes always distilled water. Let water set a room temperature for 24-48 hours helps.

Yes, I will place order today. Will not arrive in time to save this plant, but I’ll have it for next grow. Here’s a quick photo through green-lens glasses 1501608189745-766902040|281x500

Yes, I Always let my water sit 24 to 48 hours, with tap water. But do I still need to do that with distilled water?

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That’s a nice looking plant.
If your using Fox Farm liquid nutrients sledgehammer is a must, and they recommend that you flush 3 times the pot size every 3-4 weeks. I my self follow the feed chart and flush even if I don’t have a problem, mostly because if i don’t I’ll get a problem in a week or 2 with out fell. So for me it’s best to flush before hand.

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Thanks for input @Wishingilivedina420state I certainly won’t make that mistake again! Hopefully this plant will survive at least 50% of weight because I hate going to the streets for medication and the dispensary is way too expensive for me!
So just to be clear, I should use distilled water open air 24 to 48 hours, just like I would do with tap water?

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I’m with @Wishingilivedina420state
You should be flushing with ff the schedule tells to to several times during your grow it’s probably not the ad I’m that causing a issue but build up in the soil flush with sledge hammer 1 gal mix and I gallon of ph water and recheck Run off
Or 5 times the pot size of just proper ph water will also work
You have well or city water if we’ll do you have a water softener?

City water yes, water softener no.

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I’m interested in the responses here @GW… I had similar issues in ffof… My runoff sits at 5.7-6… I ended up flushing with 8-9 gallons of water and had to gradually raise the ph up and up and up… I’m not sure why this is happening? I ended up adding pulverized dolemite lime but my plants re in flower and I’m just riding this one out. I did get them in a good range but s soon as I added big blo and tiger bloom and ph’d the nutes to 6.5-6.6… The runoff was back to 5.9-6.1 range… I’m clueless but interested in feedback

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Unfortunately, in my attempt to be budget-conscious I was using tap water to flush. Things went good at 1st flush. Then I started flower stage on July 1st. That’s when I started kelp.
This past week was 2nd flushing, but things went downhill and have not recovered since.

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I don’t think you have to let distilled or ro water sit out I believe you can use it right away or at room temperature The reason for leaving tapwater sit out is to burn off the chlorine end it depends on what your city uses for chlorine chlorination can be burned off by letting it sit chloramination is another way some cities use which is harder to burn off


Could be high chlorine levels in the water
You should get a air pump and stone and place it in water bucket and let it run over night to help get the chlorine out or get a good filter system that removes it :+1:Also flush you pots
Just a few thought s @GW
If you have RO water you should have zero mineral or anything in the water :+1: @eric2 and it wouldn’t be a problem to use right away
City water is treated with chlorine and other stuff you can get a city water report from you town and it will tell you exactly what’s in the water

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@eric2 is right you don’t have to let ro or distilled water set out just tap water.
Personally I used tap water and let it set out .
My plants prefer it .

@GW when your flushing with tap water, or distilled what is the ph going in at?

@Zombo I’ve had no problem with Big Bloom. Sure, it raises my pH a bit, but simple fix with pH Down.
On the other hand, “kelp me kelp you” drops my pH significantly.
I’m seriously considering to feed BigBloom separately from KMKY on my next grow. For example: day 1 BigBloom, Day 2 KMKY Day 3 water, etc.
Here’s a photo of the Clones


@Wishingilivedina420state I use my tap water to but I’m on a well my ppm are up at 320 ish after my filters lol and my plants love it as well it’s all good minerals in my water
Well water and city water
@GW am I reading that right ff big bloom is raising you ph ?
Ff is known to lower ph significantly after be added and I’ve always had to ph up ?

Water going in = 6.5
Have tried 6.7 past couple of days