First time farmer - Calcium deficiency?

[Firekraker]

Well, new to board and typed a huge entry and accidentally deleted it. Ugggg. OK, here we go again! You know how your original thought is never as good and thorough as the second time around........?

I am just starting my 7th week of a planned 12 week crop but I am just starting the 4th week of bloom. I am new to MMJ growing as well, just FYI. Below are my stats:

Strains: Many! Romulan, Strawberry Cough, Cherry Pie, LA Woman, White Russian, Dutch Treat/13, Sour Diesel, OG Kush, Capt Kush and Tush Kush

# of plants: 30

Grow type: Pro-Mix potting soil

Grow stage: start of 4th week of flowering

Setup: Gravity fed drip irrigation system (just discontinued it)

Bucket size: 5 gallon tall

Nuts: General Hydroponic Flora Series "Expert Drain to Waste" feeding schedule

Water cycle: 2 day cycles = nuts, nuts, flush, nuts, nuts flush etc.

Lights: four 1000 watt HPS

PPM: Never measured?

PH: Awaiting arrival of digital meter. With solution and chart appears to be 5.5-6.0

RH: 50-60%

Room temp: 72-80 degrees

Solution temp: Never measured? Pacific Northwest well water, must be below 55 degrees

Room sq. ft: 265

Pests: None


Problem: I believe I might have calcium deficiency in my solution or calcium lockout due to low soil pH. I was having a rough time with my drip irrigation system and it kept over watering or under watering my plants. Today, I removed the drippers and decided to just use a hose off of my 40 gallon reservoir with a submersible pump. While watering, I noticed almost all 30 of my plants have leaves that look like the attached photo. I looked in my book, Ed Rosenthal's Marijuana Grower's Handbook, and found that picture next to my leaf. It says it is calcium deficiency and recommends first I test my soil's pH and if that is off, fix it. Then it recommends treating my plants with Cal-Mag solution or Dolomitic lime powder.

My questions:

1. Do you feel it is calcium deficiency?
2. If so, do you feel it is truly a nutrient solution issue or more likely a soil PH lockout issue due to my chronic over watering for a week?
3. How do I test my soil PH reliably? I have the coming digital meter but it is for solution. I bought a $5 soil tester from Home Depot and it will give 5 vastly different values on the same soil sample minutes apart!
4. The book recommends Cal-Mag and Dolomitic lime but does not give details on how to give it to the plants. Any ideas?

Thanks in advance for any help for this noob. I have been a long time lurker here and finally joined in June while building my grow room after getting the confidence from this site.

Brandon

 

[Jimmycricket]

Hi Brandon,

So firstly yes that is calcium def. It probably occurred because weed usually likes an absurd amount of cal and of mag (hence why they make cal mag)

For testing soil ph just get the little soil prong thing at home depot for around 8 bucks. You stick it in and leave it for about 30 minutes, they work.

dolomite lime has a lot of calcium too, and its good for raising PH as well as buffering your ph so it does not fluctuate often. Most of my calcium comes from that and from azomite.

 

[Jimmycricket]

just realized you are in soil and your PH is 5.5 thats very very low. it should average like 6.2-6.7ish in soil.

 

[Firekraker]

Thanks Jimmy,

Retested my well water again this morning with solution and comparison chart. Those colors to me are very subjective but myself, wife and son all thought color was definitely matched best between 4 and 5 PH. Think you are right, my water is way too acidic before even adding nuts. Looking at nut charts, it appears both Ca and Mg lockout around low 5ish PH to me. Thanks for help. Think I will just flush with Cal Mag today to try and buffer out soil.