Feeding: Maxibloom -or- Sensi Bloom A&B?

bc_southbuds

Well-Known Member
pH seems normal, but your EC measurement is wonky

5g/G of Maxi should be ~ 1.3 EC using RO water
My EC meter says that it is factory calibrated, or pre-calibrated. It’s like a $20 EC Meter, so maybe it still needs calibration or something. I was squinting at it and wondering why it said that and figured you all just add your own decimal (first time ever using one).
 

bc_southbuds

Well-Known Member
I've tested my per gram maxi PPM a few times and it's always ~105ppm (~.2EC) per gram. I did it last night again and got that same count. I looked at the MaxiBloom feed chart on the GH website and looking at their EC/PPM ranges that matches with what they're saying.

For instance, on the 'light' schedule, they say 4.5g Maxibloom + 2ml Ca/Mg nets them a range that's 700-850PPM (1.4-1.7EC).

When I do a gallon of water I get: 330ppm (500 scale) for my water; which is comparatively high right now due to season and our well... Then the Ca/Mg is ~62ppm per mg x2, plus 4g of MB at 105ppm. So 330+124+420= 874ppm (1.748EC) which seems to validate their math too.

So...

(Quick edit that Billy the Mountain's calc at 130ppm for maxi is probably reasonable too. When I measured last night there may have been a grain or two that wasn't fully dissolved, but definitely in that ~25ppm plus or minus area.
Hmm, all I can say is that I either 1) have a bad EC (cheap model), 2) it needs to be calibrated (even though it said it was factory calibrated), or 3) I need to re-read the directions.

I chose not to add Cal-Mag because I think there is supposed to be a good enough amount of at least MAG in Maxibloom, but I may be mistaken. Also, I’m just playing it super simple for my first ever grow. Big believer in keeping it as simple as humanly possible.

Since my Ph is fine, I bet I can do any of the suggested measurements here and still do well. Just need to keep an eye on the plants response!
 

bc_southbuds

Well-Known Member
I've tested my per gram maxi PPM a few times and it's always ~105ppm (~.2EC) per gram. I did it last night again and got that same count. I looked at the MaxiBloom feed chart on the GH website and looking at their EC/PPM ranges that matches with what they're saying.

For instance, on the 'light' schedule, they say 4.5g Maxibloom + 2ml Ca/Mg nets them a range that's 700-850PPM (1.4-1.7EC).

When I do a gallon of water I get: 330ppm (500 scale) for my water; which is comparatively high right now due to season and our well... Then the Ca/Mg is ~62ppm per mg x2, plus 4g of MB at 105ppm. So 330+124+420= 874ppm (1.748EC) which seems to validate their math too.

So...

(Quick edit that Billy the Mountain's calc at 130ppm for maxi is probably reasonable too. When I measured last night there may have been a grain or two that wasn't fully dissolved, but definitely in that ~25ppm plus or minus area.
Ok, so the 5g/gal Maxibloom mix has sat for a few hours. I double checked the EC meter instructions again and did another reading. This time 735ppm and EC 1556. Seems to make more sense compared to my original reading.
 

LeastExpectedGrower

Well-Known Member
Hmm, all I can say is that I either 1) have a bad EC (cheap model), 2) it needs to be calibrated (even though it said it was factory calibrated), or 3) I need to re-read the directions.

I chose not to add Cal-Mag because I think there is supposed to be a good enough amount of at least MAG in Maxibloom, but I may be mistaken. Also, I’m just playing it super simple for my first ever grow. Big believer in keeping it as simple as humanly possible.

Since my Ph is fine, I bet I can do any of the suggested measurements here and still do well. Just need to keep an eye on the plants response!
Eh. I ended up springing for a BlueLab EC meter. ;) I have two cheapo ones and they were both reading within a few points of each other, but who knows. ;) If everyone here thinks that we're looking at ~.26EC per gram, that works for me to calculate where things are. My water is a bit of a mixed bag since some times of year it's ~220ppm and other times its closer to 300PPM, etc. I usually discount my water's native PPM/EC since I don't think much of what it carries to be bio-available (As proven by having calcium & magnesium deficiencies when I'm not being super careful).
 

bc_southbuds

Well-Known Member
Eh. I ended up springing for a BlueLab EC meter. ;) I have two cheapo ones and they were both reading within a few points of each other, but who knows. ;) If everyone here thinks that we're looking at ~.26EC per gram, that works for me to calculate where things are. My water is a bit of a mixed bag since some times of year it's ~220ppm and other times its closer to 300PPM, etc. I usually discount my water's native PPM/EC since I don't think much of what it carries to be bio-available (As proven by having calcium & magnesium deficiencies when I'm not being super careful).
 

LeastExpectedGrower

Well-Known Member
Where does the decimal come in? I’m always seeing 1.0 or .5 etc. Here’s how mine reads

View attachment 5142843View attachment 5142843
I measured 950PPM (1.9EC) in my tank.

That's (give or take):
330ppm (water)
85ppm (Epsom salt, @ 1g)
62ppm (Ca/Mg, @ 1ml)
450 ppm (3 x1g per gallon Maxibloom, plus 1 g extra across 6 gallons)
-----

I generally subtract the water, so 620ppm (1.24EC)
 

LeastExpectedGrower

Well-Known Member
Yeah they’re definitely dosing for bigger commercial grows, I’d imagine you could push pretty hard in one of those fancy multi million dollar corporate grow facilities.
I also consider the fact that these charts aren't necessarily 'cannabis specific.' Lots of things that people grow with this stuff...and some plants (like hot peppers) can be heavy feeders. We're just used to only thinking about one plant.
 

bc_southbuds

Well-Known Member
I measured 950PPM (1.9EC) in my tank.

That's (give or take):
330ppm (water)
85ppm (Epsom salt, @ 1g)
62ppm (Ca/Mg, @ 1ml)
450 ppm (3 x1g per gallon Maxibloom, plus 1 g extra across 6 gallons)
-----

I generally subtract the water, so 620ppm (1.24EC)
1.556 EC is what you have there.

Ok thanks.

Have to admit, I was kind of annoyed and intimidated that I had to buy an EC and Ph meter, but now I‘m catching on and and feel like a whole new world of control has opened. I’m used to gardening vegetables and flowers loosely and organically, and just let the plants do the talking. It’s very subjective. This gives me objective data basically.
 

Billy the Mountain

Well-Known Member
.
I measured 950PPM (1.9EC) in my tank.

That's (give or take):
330ppm (water)
85ppm (Epsom salt, @ 1g)
62ppm (Ca/Mg, @ 1ml)
450 ppm (3 x1g per gallon Maxibloom, plus 1 g extra across 6 gallons)
-----

I generally subtract the water, so 620ppm (1.24EC)
You're water is .66 EC?
That's double what's advisable for hydro use
What's in it?
Maybe cut it with RO to get it down to .3 EC?

You can't ignore source EC when calculating or measuring your nute EC; if the meter reads 1.8, you're feeding 1.8, the roots get 1.8
 

LeastExpectedGrower

Well-Known Member
.


You're water is .66 EC?
That's double what's advisable for hydro use
What's in it?
Maybe cut it with RO to get it down to .3 EC?

You can't ignore source EC when calculating or measuring your nute EC; if the meter reads 1.8, you're feeding 1.8, the roots get 1.8
It's well water, and while that suggests lots of Ca/Mg, I've been hit with deficiencies of both.
 

LeastExpectedGrower

Well-Known Member
Consider getting it tested?
Jack's offers water testing for $30 or $40
You (or I) have no idea what's making up .66 EC worth of ions
I've laid eyes on a test before, when we bought the house, if you think I can lay hands on that test now...that's a different story. Right now the well is sort of at its high point, late summer/fall it ends up around 220ppm or so. Checked my res this morning for the blumats, and depending on what cheap tester I use, it's either 840PPM (1.68EC) or 950ppm(1.9EC).

I'm not necessarily tied to 'hydro' I like Promix which is somewhere between hydro and soilless, and the blumats are really being used so I can travel this spring/summer...I'd been hand watering for the last handful of grows.
 

LeastExpectedGrower

Well-Known Member
Consider getting it tested?
Jack's offers water testing for $30 or $40
You (or I) have no idea what's making up .66 EC worth of ions
Oddly, I refilled my 1g bottles with unsoftened water from the well today and the EC was sitting at .44 (which is our apparent baseline), when measured with both meters. I won't have the BlueLab meter until Friday and I'll check then as well. I wonder if having heavy rain yesterday changed the end composition of the water, though our well isn't shallow and we've never come close to running dry in the 6 years we've been here.

Using that number ends up at 1.5ec. I may end up cutting the water with some filtered or R/O (I have a zero filter which indeed does bring it down to 0ppm, but is only good for about 25g before the filter goes), and do something like 1g filtered for 3g of well water, which would drop things to .33EC to start.

I dug through our house/closing paperwork and the only documentation I could find was a test for potability/bacteria counts, unfortunately.
 

yum000

Well-Known Member
I have used Maxigrow/bloom on and off for years but I hate the amount of pH up I have to use. My city tap water is at 8.3 and 1 teaspoon of bloom per gal. takes me down to 5.8. I'm in soil so my target is around 6.6. 4+ mils of GH pH up is required.
You really don't need to ph in soil when it's that close, it'll raise within a short time after being applied to the soil anyway.
 
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