No announcement yet.

pH out of range / Flush did not solve

  • Filter
  • Time
  • Show
Clear All
new posts

    HELP! pH out of range / Flush did not solve

    Sorry for my English, I use the translator.

    Some time ago I realized that something was wrong when the lower leaves began to yellow, soon after upper leaves also began to create some gray and brown spots and burn the edges. From the images I saw on the website growweedeasy I noticed that my plants were exhibiting various nutritional deficiencies.

    After reading some information on the website I measured the pH of my substrate and to my surprise it is at 6.95. I measured the pH of my substrate only the first time I added water to seed germination.

    Stop solving the problem I chose to make the flush, but I did not succeed and I'm really desperate. My pots have a volume of 25 Liters and I used 90 liters of water making the flush. I measured the pH every 10 liters drained and the pH even after the 90 liters continued at 6.95.

    I heated the water that drained from the pot to a temperature of 100º celsius for 5 minutes and the pH up to 7.44

    I'm concluding that I did not prepare a good substrate because when I add water in a sufficient quantity to drain the plants they have overwater

    So I started adding little water so they would not overwater again and I think that made my problem worse.

    Friends, do you know what I should do to lower the pH of my substrate? It's been 3 days since I started 12/12 and if I can not solve this problem I believe my work will fail.


    Once a week I add nutrients in the following proportion: 3 grams Calcium nitrate + 2.5 grams of Peters (present jack's vega) + 1.5 grams of magnesium sulphate + 3 ml of superthrive per gallon, in this mixture I get pH 6.2 and EC 1.5 . On the other days I only put tap water with pH 6.2 and EC 0.1

    Composition of my substrate: 60% Peat Sphagnum, 20% perlite 20% vermiculite

    Lights: 1 HPS 1000w

    Temperature: 25º Celsius / relative humidity: 52%

    What did you ph your flush water to? 90l is a lot of water.
    how are you measuring the pH of your substrate? runoff? probe?
    3 ml of superthrive sounds like a lot.i think it is a drop or so to per gallon.
    Sweet tooth autoflower ×3 1/2 of 4.

    Regular seeds phenotype hunting.
    Bruce Banner ×5
    Fruity Rhino ×5
    Revolution ×5


    • Axl
      Axl commented
      Editing a comment
      Yes have phosphorus, NPK 10-30-20.

    • Axl
      Axl commented
      Editing a comment
      Thanks for You help but but in this setup I should work in a range between 5.5 and 6.5.

    • Mr.furley
      Mr.furley commented
      Editing a comment
      Still here D.A.A.S.69 and I agree the pot should dry out.

Check out our new growing community forum! (still in beta)

Subscribe to Weekly Newsletter!