I’m going to be using maxi and jacks with well water which comes out at 50 ppm so I’ll be needing to sub in calmag. I know jacks has to have the calnit added to the base but is there any magnesium that’s in powder form? I’m trying to keep as much as I can in powder form since it’s cheaper and more stable. Calmag in liquid form is so dam expensive.
4 Likes
Epsom salt is powder/crystal(dissolvable) and is magnesium. 
8 Likes
Honest question, is their salt in Epson salt or is it just pure mag? I ask because I found out just today on a ph question that baking soda has a lot of salt as in sodium.
3 Likes
I believe that its magnesium sulfate
8 Likes
Yes…I just went and looked at a bag I had. You said Epsom salt and I was like …shit I have a bag right here. It’s a sulfate. So I guess the calnit from jacks with some epsom salt would or should work.
3 Likes
Is there a general rule of thumb about how much to use for different situations in hydro? I don’t want to add to much and get a lockout of something.
A: If the base nutes has some in it and you just want to add a little extra?
B: Base nutes do not have any and you have to add it?
Edit: I found on rollitup where they were discussing this and it was recommended that if there was no mag in the nutes then basically 6 grams per gallon would be added. This was suppose to get you 150 ppm which is what the flora series has. I supposes if you have some and want to sup maybe 1/4 a tsp per gallon?
1 Like
150 ppm of Mg is way too much and will most certainly cause a lock out unless your running ridiculous amounts of K and Ca. 75 elemental ppm of Mg is about the max.
2 Likes
If we’re allowed to post to other sites…this is what I was reading.
Have any idea what gets you about 75 ppm? 1 gram half a gram? And, to be clear you’re saying 75 ppm max per gal total. So, if the base already has some in there it’s going to be hard to tell where I’m starting from? I’ve used this in the past on city tap at recommend rates with maxibloom and had no issues. But, I’m on well water now that doesn’t have much in it. And, I wanted to try and save money. I’m not sure on how to measure this out correctly.
Yeah fatman usually had some good info but I don’t know why he is recommending such high Mg numbers.
1 Like
2.9 grams of Epsom per gallon of RO water will get you 75 elemental ppm of Mg and 100 ppm of Sulfur. An even 3 grams will get you 78 ppm of Mg and 103 ppm of S which is close enough.
2 Likes
What about too much sulfur, my well water has some which is why it’s acidic at 4.9 ph. Then I believe both maxi and jacks has sulfur in the base.
Is there a online calc to help with this especially when using dry nutes that you guys recommend? I’ve heard of hydro buddy but don’t see a port for the linux I’m using. The author needs to put it in a snap or appimage package.
1 Like
Don’t worry about the sulfates. I’ve never had problems and I’ve used a lot over time in my soil. It’s easily leached from the media.
1 Like
Thanks, I’ll be using coco in a hempy bucket.
Looks like I need to get a set of these.
2 Likes
Wow. Those are cool. Didn’t even think if they had smaller than 1/8. Just added them to my Amazon cart.
2 Likes
Right!
They’re going in my cart now too. 
1 Like
You can run S as high as 200 elemental ppm. It doesn’t cause any antagonism of the other elements unless it is extremely high and is usually only available at a pH of 6.5 or higher. I believe mine is close to 175 elemental ppm.
1 Like
i used to spin up a vm when i found something i needed windows for while running linux. maybe this will work for you here.
@Taproot
Check out some of the thread here related to Jack’s. Search posts for things like “elemental ppm”, or “nutrient profile”.
@Renfro Has a thread on RIU where he made an excell spreadsheet calculator for elemental ppm. You can download and use that for free. And then there’s HydroBuddy:
https://scienceinhydroponics.com/2016/03/the-first-free-hydroponic-nutrient-calculator-program-o.html?print=print
Know how much of ‘X’ element (eg: Magnesium) you’re actually adding per amount (eg: grams) per volume of water, when you add any compound (eg: Magnesium Sulfate). How much magnesium, and sulfur, and whatever else.
I was wondering “What the fuck is Powered Magnesium? Sounds interesting.”
If you’re using Jacks 5-12-26, it has (magnesium) magnesium sulfate in it. You can add more (of anything) though. I duno what maxi you’re referring to.
2 Likes
Magnesium that’s not already in a solution…like a quart of calmag from amazon. I don’t like paying for water if I don’t have to. I used to use liquid ferts but realized how expensive they were and they didn’t store that well for those of us that like to have a small grow or two a year. I love dynagro…wished they’d had a powered form back then. A user on RIU got me on maxibloom and I found it just awesome and affordable. I’m going to try Jacks to as I’ve not tried that yet.
Thanks for your input!!
1 Like