CactiGuide.com

Ii wonder how accurate this device is ? Turns out it doesn't work.

keith wrote: ↑Thu Jul 22, 2021 3:16 pm Ii wonder how accurate this device is ?

Get a set of pH buffers: 4.0, 7.0, 10.0 and test your meter. You will know the answer to your question.

And I just searched and found a very handy way to use buffers if you don't use them frequently. These buffers come as tablets and need to be dissolved in 20 ml of Distilled water. You will need a way to measure this 20 ml. A medicine cup may well be calibrated in ml and go up to 20 ml at least. Check your pharmacy. This is a great way to calibrate your instruments if you only do it occasionally and don't want to buy the liquid buffers.

https://www.amazon.com/Buffer-Calibrati ... 42&sr=8-36

I have a liquid fertilizer with NPK of 7 6 11 with micronutrients where Ca / Mg ratio is around 3. My tap water ph is around 7 to 8 which I acidify to bring it to 5.5. Do you think if I add this liquid fertilizer, it will do good for my plants?

abhikjha wrote: ↑Tue Aug 03, 2021 7:47 am I have a liquid fertilizer with NPK of 7 6 11 with micronutrients where Ca / Mg ratio is around 3. My tap water ph is around 7 to 8 which I acidify to bring it to 5.5. Do you think if I add this liquid fertilizer, it will do good for my plants?

See Mike's response here:

http://www.cactiguide.com/forum/viewtop ... 15#p388602

Good answer in what he said, so follow his recommendation.

Everything is for sale now, no need to drain old auto batteries...

I did some tests with the following products:

the pH meter: the Checker Plus by Hanna Instruments (Before each testing session I do a two-point calibration.)
to acidify the water: JBL pH-Minus (I have a small collection and the bottle is quite compact, might not be interesting for larger collections.)
additional products used: Vitanal (https://www.kakteen-haage.de/en/accesso ... 00-ml.html)

The first test was in 2020 and the second in 2022. Why my tap water changed from pH 7,1 to 6,5, I don't know. I did double check to make sure. Also, during the second experiment the order in which I added the products seem to influence the result. Again, I don't know why, but should probably run the experiment again.

Here are the results:

WATER pH 7,1 (city tap water, left 24h before testing)

session 1
pH 6,5 = 1L water + 11 drops JBL (0,55ml)

pH 6,0 = 1L water + 17 drops JBL (0,85ml)

session 2
pH 5,5 = 500ml water + 8 drops JBL (0,4ml) + 1,5ml Vitanal

WATER pH 6,5 (city tap water, left 24h before testing)

session 3
pH 5,7 = 500ml water + 4 drops JBL

pH 5,2 = 500ml water + 6 drops
 JBL
pH 4,1 = 500ml water + 6 drops JBL + 1,5ml Vitanal



session 4
pH 6,1 = 500ml water + 1,5ml Vitanal
pH 5,9 = 500ml water + 1,5ml Vitanal + 2 drops
 JBL
pH 5,3 = 500ml water + 1,5ml Vitanal + 4 drops JBL

I tend to use citric acid, not with every watering, but quite often.
I use food grade citric acid that I buy at stores that sell Indian foods.

I don't test the pH, I just use around a teaspoon per gallon, or less when I combine it with soluble fertilizers, but I typically taste a few drops of the solution and have yet to notice a sour flavor.

I consider citric acid to be both a pH adjuster and plant nutrient.

Nobody wrote: ↑Tue Jan 03, 2023 5:05 pm I typically taste a few drops of the solution and have yet to notice a sour flavor.

Surly your not tasting water with fertilizer in it? That can’t be good for you man.

keith wrote: ↑Mon Aug 10, 2020 6:54 pm https://abqbonsaiclub.com/bonsai-soil-article/

Just read this article tonight, and went over the whole thread again. Thanks for posting the Bonsai club potting soil experiment article Keith. Good information regarding Turface and how it holds so much water and decomposes fairly quickly. I bought two 50 lb bags of it a few years ago. I have used one. I don't remember how much I used in my cactus mix. I'm going to have to check.

hi Jerry, yea they don't like it at least for bonsai . years ago I noticed it caused fungus on my cactus seedlings so don't use it.

Might be fine in a dry place like Phoenix AZ ?

Turface can be used in Planted Aquariums. Should be OK for African Violets too.

I apologize for resurrecting relatively old thread, and I'm not sure if this is right thread at all, but I would like to discuss the effect of chlorine in tap water on our plants. It is somewhat confusing subject for me for I always thought water should be kept in an open dish for at least 24h to "let the chlorine evaporate". Now I have found out two facts:

1. Chlorine that is added to the tap water is remarkably stable and evaporate very slowly (it would certainly take much more than 24h for it to go away completely). Only reliable and effective way to get rid of it is to run the water through the activated charcoal filter.
2. Added chlorine (at least is my area) is relatively small: 0.2 mg per 1 liter of water. That would be 0.0002 g/l or 0.00002%

I can't find any data about acceptable levels of chlorine in water used for plants, but I often see that fertilizers and/or commercial substrates state "Low ammount of chlorine", which means that they contain some ammount of it.

Thank you everyone in advance for any insight regarding this issue.

Nino_G wrote: ↑Tue Mar 12, 2024 9:24 am I apologize for resurrecting relatively old thread, and I'm not sure if this is right thread at all, but I would like to discuss the effect of chlorine in tap water on our plants. It is somewhat confusing subject for me for I always thought water should be kept in an open dish for at least 24h to "let the chlorine evaporate". Now I have found out two facts:

1. Chlorine that is added to the tap water is remarkably stable and evaporate very slowly (it would certainly take much more than 24h for it to go away completely). Only reliable and effective way to get rid of it is to run the water through the activated charcoal filter.
2. Added chlorine (at least is my area) is relatively small: 0.2 mg per 1 liter of water. That would be 0.0002 g/l or 0.00002%

I can't find any data about acceptable levels of chlorine in water used for plants, but I often see that fertilizers and/or commercial substrates state "Low ammount of chlorine", which means that they contain some ammount of it.

Thank you everyone in advance for any insight regarding this issue.

First of all, I keep meaning to post a new "how to" presentation since the one I originally posted in 2019 is missing key information I wasn't aware of at the time. Unfortunately, I don't have the time to do it yet, but I will soon.

Regarding the chlorine issue, see this:

https://www.gardenmyths.com/chlorine-chloramine-plants/

The article mentions a potential chlorine problem in hydroponics, but none of us are growing cacti hydroponically even if the potting medium is a pure "semi-hydroponic" mineral gravel mix.

Steve Johnson wrote: ↑Tue Mar 12, 2024 9:24 pm Regarding the chlorine issue, see this:

https://www.gardenmyths.com/chlorine-chloramine-plants/

The article mentions a potential chlorine problem in hydroponics, but none of us are growing cacti hydroponically even if the potting medium is a pure "semi-hydroponic" mineral gravel mix.

Thank you Steve! Very informative article, I learned a lot.