Celt’s Cavern Of Chaos

The Celt said:
Amazon can Flock Off
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That company gave us the big FO quite a few years back when they suddenly decided they really don't want to ship here anymore. Some lever clicked somewhere in the great machine and rates went from usually free to - pointlessly high, or ‘needs special handling and doesn’t ship to your location’. Now most stuff is like a $110 grow tent I was looking at yesterday which wants $390 for shipping.
 
Ya, really less and less impressed with them. I paid for Prime to get the “Free Two Day Shipping” and for at least a year now that’s been a week plus getting here. Even their Prime Video isn’t much anymore, gone back to Netflix most of the time.

Considering the majority of what’s on Amazon comes from Overseas (China mostly) anyway, I might as well get it off Aliexpress, still fee shipping and you know up front it will be 30+ days, they don’t lie about it. And BONUS, membership costs me nothing :rofl:
 
Morning all :)

As I said yesterday, things are pretty much on standby until the new year when things I ordered finally arrive.

When I started this, I approached it like most things, “Flying by the seat of my pants and learning as I go” :rofl: I knew lots about plant chemistry and organics, but very little about hydroponics other than:

- plants tend to grow faster
- DO levels need to be high enough to prevent anaerobic conditions leading to pathogens
- and pH needs to be maintained in a certain range for nutrient uptake

Faster growth is a big draw for hydroponics, but the time involved, mixing nutes, cost of nutes, etc were all negatives for me as well as wanting to grow organically so until now it’s not been overly attractive to me.

Now I know some will say “but you can buy organic nutes”. This is true, but, they are still salt based nutes derived from organic sources, and yes some brands claim to have organic cheating agents as well. Kudos to them, but that is really nothing special, most commonly used cheating agents are amino acids which are organic by their very nature.

So for me, to be truly organic, the system requires microbes to make nutrients available to the plants. As of yet, I have not come across anyone growing hydroponically using microbes to break down organic matter for plants growth.

So me, being me, says to myself “let’s give it a go, worst case scenario, it fails to grow plants, but we’ll have fun and learn just as much from failure as success”.

Having now run the system some to watch pH and temperatures, my biggest concern aside from DO levels, I have noticed 2 issues : pH drift (up) and temperature rise.

Temperature rise I can deal with, I will make a heat exchanger to run solution through to cool it.

pH drift is something I probably could have prevented in the very beginning if I had foresaw the issue ahead of time, but something that I will likely be able to correct when an order arrives sometime after the new year.

Warning, the next post will be a chemistry lesson :rofl: I am going to go over “buffer solutions” and cheating agents ;)

BBS, outta smokes and milk for my coffee :rofl:
 
As promised, time for some chemistry.

This will cover: pH, Buffering solutions and chelating agents.

NOTE: those of you growing in organic soils can ignore this lesson if so desired. You can not regulate the pH in organic soils better than the plant does, all you can do is muck up the pH and cause problems with your plant.

Back to the lesson ;)

First off we’ll start with pH so those that don’t have a good understanding can follow along with the rest of the lecture :)

To understand pH, we need to start with pure water H2O or 2 hydrogen atoms and 1 oxygen atom. Even in pure water, not all of the hydrogen is bonded to oxygen, some of the hydrogen is milling about as H+, or single hydrogen atoms with a plus 1 charge, it’s counterpart (or other half is you like) is OH-, or a hydroxyl ion...1 oxygen atom bonded to 1 hydrogen atom and having a charge of -1.

When we measure pH, we are measuring the number of H+ ions (or lack of) in solution. In pure water, even though we have H+, OH- and H2O , the H+ and OH- are in equilibrium so we get a neutral pH of 7.

Now if we add an acid, our pH lowers because we now have an excess of H+ ions in solution. Conversely, if we add a base, our pH rises due to an excess of OH- ions.

Now it may seem simple, but pH is measured on a logarithmic scale meaning that for every point rise or drop we have gained or lost 10x the H+ ions.

Example: pH of 6 has 10X as many H+ ions as a pH 7 and a pH of 5 has 100X more H+ ions than pH7 etc.

So now that we have covered the basics of pH, time for Buffering Solutions.

A buffering solution is a solution with a set pH that resists changes in pH when weak acids or bases are added to it. Because of its nature to resist pH change, and can be tailored to a specific pH, these solutions are widely used in chemical analysis, especially in biological research & testing.

Any of you who have calibrated your pH pen with commercially available solutions has used a buffering agent :)

Buffering agents need to be chosen carefully because some can also act as chelating agents causing issues with other compounds in your solution. I’ll explain chelating agents later.

Buffering agents work similar to the explanation of water above. It consists of an acid and it’s conjugate base - in water H+ is the acid and OH- is the conjugate base. For this exercise, I am using Citric Acid and it’s conjugate base Sodium Citrate, which also suits our needs for hydroponics due to its ability to be tailored to 6 pH (or a range from 3 to 6.2pH), and it’s common and easy enough to produce.

Now, you may say “what about the sodium, we want to limit how much our plants are exposed to” and you would be right but for explanation purposes we will ignore that issue but address it at a later date when I receive the Citric Acid I ordered and can do a bit of experimenting :)

I guess maybe I should explain what an acid and it’s conjugate base is :)

Our acid is Citric Acid => C6H8O7.
Sodium Citrate (our conjugate base) => Na3C6H5O7

Now I have aligned the 2 formulas so you can see the difference, Citric Acid has 8 H atoms and in the base, 3 of these have been replaced by Na (sodium). Once we have our buffering solution set at our chosen pH, here is what takes place when we add more acid/base.

In the case of addition of a base, using NaOH as a base for simplicity, the NaOH dissociates into free Na+ ions and OH- ions. These ions then combine with the Citric acid in solution producing more Sodium Citrate and Water:

NaOH + C6H8O7 => Na3C6H5O7 + 3 (H2O) maintaining our balance

When we add an acid, say HCl (hydrochloric or Muriatic acid), it combines with our conjugate base and we get:

3(HCl) + Na3C6H5O7 => 3(NaCl) + C6H8O7 again maintaining our balance. (salt doesn’t contribute to pH, no H+ ions)

Now in my setup, I will be using Citric acid, but not Sodium Citrate. It’ll take a bit of testing but I think I can solve the sodium issue. As for using Muriatic Acid, I may use it if needed, Chlorine doesn’t concern me as in a well aerated system, it will evaporate quickly.

BTW, anyone wanting to make a pH testing solution for calibrating pens:

mix 17.45g of Citric Acid (powder) with 20.77g of Baking Soda in 800ml distilled water. Once fully dissolved, top up your container to 1 litre and you have a buffered solution with a pH of 6.0 :)

Now that we have covered pH and Buffering solutions, on to Chelating agents. Although they play little to no role in my setup, they are a major concern for salt based hydro systems, and also because some buffering agents can also be chelating agents as well that “could” cause issues for me.

In simplest terms, a chelating agent is a chemical compound that prevents metal ions (Na, Ca, Mg etc) in solution, from interacting with other compounds that may cause them to drop out of solution as precipitate (insoluble forms).

As a example, if you have copper ions in solution and add salt (NaCl), Copper Chloride will form and precipitate as a solid (not soluble in water). By chelating the Copper, we can prevent this from happening.

I have included this also because the Citric Acid I intend to use, can also be a chelating agent.

Well folks, that’s today’s lesson, more to come, you can be sure ;)
 
Well-written and well-explained! I feel a bit smarter than I did when I woke up this morning. :thanks:
 
The Celt said:
Morning growmates,

Heads up, one of our Sponsors , The Vault, is having one hellava Xmas contest and anyone can enter.

100s of seeds and multiple prizes :thumb:
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Gmornin Celt, Great lesson! I always wondered why the ph changes so fast in, say, a 5g bucket. I live in the desert and have really hard water so I run all water through softener/water treatment system that unfortunately takes the stuff that is beneficial to plants out and, because of my hypertension, I use potassium instead of sodium chloride . I use calmag throughout my gardens. I'm paying close attention because I'm a coco guy and I've got to go to the next level and try to max the health of my girls. So im in the front row.Thanks again. Enjoy the day and stay stoneder.
 
I can't find the vault in the sponsor page. Am I really stoneder on Bubba Kush or?
 
Morning friends :)

As things are on hold, at least for another couple of weeks, I will be working on tearing down the system so I can move it to the other end of the tent. I want it at the end closest to the window because that is where I will be putting the cooling system which is going to be a must to keep temperatures down and DO levels up.

I also need to modify the riser to send solution through the cooler before it supplies the buckets. As I don’t want the solution going septic again (smell) I will be pumping it into a tote and then using the internals of the system to keep it aerated in the tote.

Again I will be repurposing stuff I have lying around to make the cooler. This old place had a boiler system for heat which is being replaced with a heat pump and while I have been renovating, I cut out the old finned radiators. 3/4” copper pipe with aluminum fins. These will become my cooler :)

I will continue to include the science (chemistry mostly) involved as I go and come across issues related to my grows, it helps those without a background in the sciences have a better understanding as to what is taking place in their soils, feeds and plants.

For those following along, if there are things I don’t think of that you would like to have a better understanding of, give a shout and ask :) I will do my best but let’s keep in on topic in regards to plant chemistry, botany and technical issues with lights, environmental controls , etc that are related to growing.

All for now, keep it green and spark one up :)
 
Thanks!
 
Houston, we have a problem. Launch of the RDWC system will be delayed yet again, maybe :rofl:

Yesterday, while tearing the system down, I transferred the solution to a tote with the intent of having it cycle in there, staying aerated until I moved things around and built a cooler.

The bloody pump died :rip: not sure the issue, thought it might be in the float switch but it’s getting power and the motor itself is a sealed unit :(

I do have another pump on hand so we’re not yet dead in the water, if it still works. Problem is, it’s not a submersible but rather a hot tub pump that’s been sitting in the back shed for years. This means reworking the system with the reservoir outside the tent and more plumbing but likely a more reliable pump as it would be continuous duty. It might also save on cooling being that the pump is external to the reservoir and the reservoir will now be external to the tent.

Now I am debating on starting plants anyway in the little tent on christmas day. That would give me about 3 wks to get the DWC system working, still Waiting on citric acid and a DO meter anyway. Decisions, decisions :rofl:
 
It's always something Celt.
 
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