How Fucked Is My Water?

[MindSoup]

Hello chums

 

As per the title really. Looking at my water report how bad ist water? And what would you do to make it better for growing? 

 

 

For the most part I do alright with it, but I do get pretty bad rust on my leaves from time to time and I think this could be a contributing factor.  I was thinking adding mag might not be enough, maybe It would be worth getting an RO filter, doing a 50 50 mix and then getting the cal mag ratio in line. 

 

As always I've seen mixed opinions on the importance of the whole cal/mag thing, but this is a pretty extreme case so I think it's worth looking at. 

Edited July 18, 2023 by MindSoup

[Bobcharlieeeee]

Id say you need a better calmag ratio closer to 3:1 cal/mag

 

However aparently you cant take the calcium quantity directly off the report, for example, my report from the internet shows calcium at 250, but growers ark tested it at 100.

 

My magnesium was correct between the report and growers ark at 2.

 

Growers ark recomended i add 0.15g/l of water whilst using there hard water nutes. id get growers ark to test it so you are 100% sure. they also tell you how much epsom salt to add

[MindSoup]

Sorry totally forgot about this thread . I think your talking sense, cal mag ratio is definitely fucked, but I'm aware my base EC is probably already be sky high, so was thinking just adding more mag might not be the best solution, maybe I should dilute it first with RO? Not hugely clued up on all this either. 

 

In theory my dry ferts mix and mulch should already be providing quite a lot of magnesium (and other minerals), wether that's the best method of delivery I'm not sure. 

 

I'm also very much aware that these sort of issues can be massively amplified by environmental imbalance, I've only experienced this problem since switching to a new more powerful light that covers more of the tents footprint, so although my hot spots are a lower ppfd, the average pofd is probably a lot higher. Couple that with high temperatures and low humidity and maybe the water isn't even the issue . 

Edited July 22, 2023 by MindSoup

[latigid aikon]

1 hour ago, MindSoup said:

but I'm aware my base EC is probably already be sky high,

The EC of your water is just over 0.9 according to the report you posted above.

 

You'd need to dilute it a lot with RO to get it to sensible levels.

 

The samples that contained more than the legal limit of Coliform bacteria are a bit grim, I think that comes from either human or animal shit.

 

Is this normal mains water or does it come from a well or something?

[MindSoup]

Yeah TBH I think the only reason I've been getting off lightly with it for so long is because I'm growing no till, but I fear it's starting to catch up with me. What would be a sensible ec for me to aim for? Being the lazy git that I am I might try just diluting it before I bother balancing the cal/mag ratio, see if it's enough to sort things out. 

 

Hadn't clocked the bacteria thing TBH, pretty scary. It's from a bore hole iirc, but it's mains water, I do live in a heavily agricultural area though with lots of intensive farming. 

[catweazle1]

My guess is treat it first with 10% vinegar, probably 2ml/L. This will convert much of the calcium into soluble calcium acetate. If you put the vinegar in last it will react with some of  the nutes as well, diminishing its calcium-converting capacity. Then add Epsom at 2g to 4L/ or 0.5g/L. That will give 60mg/L. You can dissolve 500g Epsom in a litre to make a stock solution and add 1ml per litre for each 30mg you want to add. 5ml plastic pipettes are great for this. You would put 4 pipettes worth in 10L of your water. 2 - 4 pipettes in 10L of vinegar is a doddle to apply as well. Then add your other stuff. Check your pH and EC. Adjust pH if necessary and note if you need to add or take away a bit of the vinegar for next time when you make up your solution. That second time adjusting pH measurement  is a once-only operation to see that you have  your initial acid addition in the ballpark; the nutes will have an effect on the total pH you need to account for. My ec is 0.7. 

 

I avoid phosphoric acid because it adds phosphorus and it's best to keep it at the level only your nutes put in. Also the compounds of phosphorus that it will create are largely insoluble and there is a high risk of nutes dropping out... calcium phosphate  and magnesium phosphate, especially are insoluble... mag and cal  deficiency magnet imo. Vinegar adds nothing to the ec as well. Normal vinegar is 5%, so you want the stronger 10% version, but you can use it. If you get the 20% vinegar, add the same amount of water to double the amount of stock and bring it to 10%. It gets pretty cheap in bulk... and it's there for your chips! Using it too strong at 20% will push the pH over too quickly. We don't want to use pH Up to correct it. You want to be using it in whole MLs, not fractions of mls, for ease of application, is my thinking.

 

If the base ec is 0.9, you will probably aim for a total of 1.7ec to provide room for the nutes on mature plants. I aim for 1.5ec, having 0.7ec water. 0.5ec water, I would aim for 1.3ec.

 

To repeat: for this to work, it's important to acidify the water first.

 

E2A. Just realized you are no-till. Ignore the section about nutes and treat your water with acid and epsom.

Edited July 23, 2023 by catweazle1

[MindSoup]

That's gone a bit over my head TBH bit of a luddite about this stuff. Is the calcium not already soluble/in solution? And how exactly does converting it to calcium acetate help exactly? 

 

Does sound a bit more of a faf than using RO but it would mean less equipment would be necessary.