hydroPlane

Enjoyable read with a large amount of good info. good post hydrosan

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Second Grow:
Operation Green Waterfall(Finished)

FirstGrow:
WhiteRussian and Bagseed in soil(Finished)
Soda Pop and NLxHaze in hydro(Finished)

Plant Troubleshooting Guide

When to Harvest

Karma's Perfect Cannabutter

Garden_galore

Great stuff Pretty useful info to know to help us with our first grow and master our second

Cheers dude!

TG

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2005 The Garden Begins (AK48)
2006 The Garden Continues (KC36)

PH Problem? Plant Abuse Sexing Trichs Spidermites 1+ 2
Nursery Q's

jamesgang

... A long time ago... Now it IS...

JG

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THE MONSTERMAN RETURNS...


The JamesGang

HydroSan

After a couple more years to understand pH in hard water, I have some more observations for this thread.
If water has higher concentrations of Calcium and Magnesium it can become a potential problem since both of them can combine with Bicarbonates to form insoluble Calcium and Magnesium Carbonates. This will also impact on media pH (increase the pH of medium) and restrict the availability of many other nutrients. Calcium can also react with phosphorous to form insoluble Calcium Phosphate. If water has higher concentration of these salts, then growers should be careful about using more Calcium and Magnesium in their feed solution.
Most of the plants grow best when the medium pH is 5.6-6.2. The main effect of water pH on plant growth is through control of nutrient availability. A low pH may be responsible for excess Iron and Manganese availability leading to toxicities or Calcium and Magnesium deficiencies. A high pH is worse as it can cause deficiency of many of the nutrients. In general, the pH of irrigation water is not as critical as the pH of medium but the addition of high or low pH water can change the pH rapidly especially in soilless medium that already has very low buffering capacities.

So, the close relationship between Ca & Mg means that an accumilation of one effects the other. In an ideal world (or ideal water) one can simply allow the pH to range between 5.6 – 6.1, allowing the plant to take the correct ratios. If however your water contains higher levels of Ca & Mg, the plant can take excess Ca or excess Mg, depending on the pH and initial Ca level in the water, and subsequent Ca level after the res has run down some and become concentrated.

Excess Mg locks out Iron, and Ca.
Excess Ca locks out Mg, and other micros.

Hi pH (consistently higher than about 6.1) will lock out Iron, zinc, manganese, boron, and copper. Magnesium deficiency is promoted by high pH, high K, or low N concentration in the growth medium.
Very Low (consistently around 5.6 and lower) pH will also lock out Phos Ca, Mg etc.

Hence a pH range of 5.6 – 6.1 for hydro.

To compound this, Acidity increases the Ca requirement. Alkalinity forces zinc and especially iron out of solution, often leading to severe deficiencies of these metals despite the use of chelating agents to help keep them in solution.

Therefore higher alkalinity effects the precipitation pH level. Since there is a high level of Ca in hard water, you need to add lots of negative ions in the form of phosphoric acid, these quickly bond to the positive cation of the Ca, forming calcium phosphate. initially the pH goes down, but as they bond, it goes up again. If you add enough negative ions, you eventually reach the ionic balance point, where there’s not much Ca, or biocarbinates, for the phos to bond to, adding more at this point sends the pH plummeting. This effect is much more noticeable in hard water. In soft water the pH will graph will curve down with the addition of phos acid, in hard water it flatlines, then falls off a cliff

Hard water growers are constantly balancing between their ionic balance point (which will be different pH values because of the different Ca concentration in the res) and their precipitation level (mines about 6.4) where nutrients form solids in the res, and hang around like sand in the bottom, leading to deficiency. (see precipitation test above)

The closer you are to either boundry, (whatever yours may be) the more likely you will experience nute deficiency. The softer the water, the bigger the window

It took me two years to understand this lot, and I notice there's quite a few growers with the same headache so I hope this helps

2 year Bump

San

HydroSan

Well, it's OK showing why we have snags in hard water, but what are we gonna do about it?

Hard Water Options

Option 1 – working with shyte water.

Firstly, get to know your ionic balance point so you can try to stay one or two pH points above it to avoid pH plummet, remember this point will change during the life of the res. If you do plummet, either change res, add more water, or use potassium silicate to bring the pH up again. Never add pH up, potassium hydroxide, as it will screw the ionic balance when added to a res containing phos acid, and you will have very little control over pH buffering or deficiency.

Secondly, do a precipitation test with your strongest flowering nutrient strength in a glass with your hard water, for 24 hours. This will show you the pH at which some nutrient elements precipitate out of solution. Try to stay one or two pH points below this level.

You will see that there is a two pronged approach to managing pH in hard water. On one hand, we want the pH around 5.8 to allow correct Mg intake, but, on the other hand we don’t want the pH to plummet, as it will if we try to maintain the pH in this region. We also have to avoid high pH over about 6.3 to avoid precipitation & Iron def. And we have to allow the pH above 5.8 to avoid Ca deficiency

In practice, I find it easier to try to maintain a lower pH range than 5.8 for the first two days of a new res (5.6 -5.9), then let it drift up to 6.3 over a further two days, or bring it up with potassium silicate if it remains low after 2 days. This sounds easy, but in reality the pH is very unstable and I’m never happy leaving the grow for over 24 hours. It is easier to maintain lower pH values when the res is fresh, as it concentrates, the ratio compounds, meaning more Ca than you stated with, and a much harder time maintaining lower ph values.

Option 2 – Make your own hard water nutrients.

This will mean a lot less Ca & Mg in the mix. You will need to start with a water analysis, so you can tailor the nutes to it and avoid excess Ca etc.

Option 3 – Use rainwater.

Guttering etc into storage barrels – rain water is pretty clean, you mite have to add in some tap water to buffer the solution, aim for an initial starting EC between 0.2 – 0.4 to buffer the solution.

Option 4 – Reverse osmosis filtering.

Can be expensive if you’re on a water meter. Some systems waste 90% of the water they use. The problem with RO is a lack of buffering, and bacterial slime, it breeds like billy’o in pure RO water. The solution is to add in some tapwater, which will also buffer the solution. Aim for an initial starting EC between 0.2 -0.4.

You can also use propriety hydroponic addatives like Cal Max to supply the initial buffering and slime deterant, these usually contain the micros, so may be useful depending on your nute regime.

Now I know my issues in depth, I have decided to go the RO route for a much easier life

San

massproduction

more great info my head is gettin g bigger by the min

DarkFox

I've just read your the recent updated bits (don't know why I hadn't earlier ) and at least consoled that I'm not on my own...

Thanks San ..

pearl

Thanks bigtime Hydrosan , I really appreciate the information.

I use the Flairform colour system and since I use Tap water and change my res just about everyday (I use a 5 gal res) I can see why I have good results with it.
I never knew why I liked it but now I understand a bit more about it.
Always knew I liked having fresh nutes and fresh PH just about daily [depending on the stage of growth I'm at].

Thanks again for the info.......pearl

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Pearl's Drip System ~ Fall Harvest 2006 ~ Live Predators

sfttailpaul

Thank you very much HydroSan for that most educational thread you posted about understanding pH AND the link to the Mg deficiency or LOCK-T as I now have come to understand. Bst thing is that all this information makes sense, and I can understand it too. Guess I need a few more hits to change all that. I have also seen here that one should NOT mix the nutes while stoned!
Being a newbie (been a toker for 41 years though) I am realizing the intense pH problems that await me. I have seen my plants solutions JUMP from the 5.6 I started with (only a few days old) into somethning near the 7.0 range! My goodness! This Hydroponics is quite fascinating, and I have learned so very, very much here. I read, and read for several months before I started to plan my grow environment. pH is definitely something I need to master, and at a far better capacity I have today.
I have a closet that measures 2 ft. Wide X 8 ft. Long X 8 ft, Tall. I basically have 1/2 for Veg. and 1/2 for Flower. For the flowering 1/2, I built a plywood box that fits inside the closet withourt any attachmnenbts or destruction to that area of the closet. The entire interior is lined with mylar, and is ABSOLUTELY light proof! I stood inside, and verified. This box/mylar/hardware cost me under$150.00 to build, and it comes apart for easy relocation (built in place with "tee-nuts"). The floor has some holes in it that alow the fresh air intake from a hole that is 4" in diameter; this route under a built-up 4" tall floor. This also gives me the height I need to be able to drain my resivour. I am growing Aero style, and I built my system from the informatiuon found here as well as from the manufacturers' of these systems. This also gets fresh air in from a 4" hole in the floor into the crawl space (I envy those who have basements).. The light reflector is connected to a turbine fan that runs througha home-made Activated Carbon (Charcoial) Pellet Air Purifier/odor control (found 100 lbs for $45.00 plus $25.00 shipping on, you guessed it, eBay). I have the fan blowing through aproximately 180 lineal inches of 5" X 4" race-way filled with Carbon Pellets. The other side is the Veg side, and containes an area for 4 mothers at the bottom (440 W. MH) with a clone/seedling space above (200W CF), and there's still room for another grow section using another reflector there. This side also has the same (duplicate) fan/exhaust set-up as the flower side, running through that air chamber in tandem. I want to suppliment the lower (mothers) section with 4-250 MH and cheap reflectors mounted Vertically to fill-in the lower, and side-lighting areas (4 corners). I would simply buy a 1,000 watt ballast, and wire these four reflectors in, in parallel. The ballasts are all home made, at a mere fraction of the price they want for them on all those Hydro sites. 400 W MH was $45.00; 1,000 W MH was $87.00. Bulbs are a "steal" on a few sites, so do your homework. Generic are in the $30.00 range; Name-Brand hover around $65.00. I am a firm beliver in more light is better. I can easily control the heat, as the 4" in-line "turbine fanbs I cxall them) are at aprox 450 cfm. At 64 cu. ft/ room, I exchange the air (when fans are on) at a ratio of 7 times a minute! This pulls quite the adequate amount of fresh, and cooler air into the grow environmnet, that I doubt I'll need (or be able to utilize) CO2. I can't get my temps above 80 degress F without turning off the fans. I aslo believe that there's enough CO2 in the fresh air, that suplimental will be a waste. I will, however, use CO2 anyway, as my syrup/yeast CO2 generator is simply too cheap, and too easy to NOT use!
I wish I could post pictures, but alas, I cannot modify them with the software I currently have (Kodak, easy share). I can't afford Photoshop, as I have all my cash tied up in this "grow".
WISH ME LUCK, asd I have a lot to learn...
SFTTAILPAUL

Drummerboy1976

could it be that we should just concentrate on keeping Ph in the proper range and not constantly mess with our nutes to compensate for fluctuation??? I have a habit of dropping nutes when ph drops and im starting to think its not a good approach all the time...

~DB~