Hard Water

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bigweedo

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Hi All!!

Starting a new grow and want to bounce a couple ideas of you guys!

It seems like my grows always start to have issues about 5 weeks into flowering. It looks like the plants get locked out and have deficiencies, but I have bumped up my nutrients in the past (still pH is around 6.5) and it doesn't seem to help. pH is always around 6.5 and they look great until the 5th week.

I use eartjuice seablast nutrients:

-Grow- 17-8-17

-Transition- 8-32-14

-Bloom- 3-26-22

-Bloom Master- 0-50-30

I'm starting to think my water might be the culprit, with some dissolved solids. My shower heads always have a white crust (sodium or calcium I would guess) and an orange/red crust (magnesium)

My PPM of the water is roughly 250-300. According to my water district website, 125ppm is calcium and 20ppm is sodium.

Could this be the reason my plants **** their pants? I would like to keep using this water, due to me not being able to afford reverse osmosis. Anyone have success with General Hydroponics Flora hardwater nutrient line?

Anyone else in a similar situation?

Thanks!

Big:vap-Bong_smoker:
 
Funny, I have the exact same issue going right now....Calcium locks out the Nitrogen, & becomes toxic in the soil to the plant...an RO system is my answer.
 
"Issues" can be a whole lot of different things. Could you give us an idea exactly what happens to your plants around 5 weeks? Also, tell us about your grow setup--size of space, size and type of lights, strain, your medium, how much you feed the plants, how large a pots, how much do you water them, temps, RH, etc.?

Where I lived before, I had a well and the water was high in dissolved solids. We ran an RO. I am not a huge fan of ROs as they can waste a whole bunch of water, but for growing, we do need water without a lot of dissolved minerals in it. So, if you cannot afford a RO, I recommend buying water.

What might be happening here is that the minerals in your water are killing the microbes in the soil. By 5 weeks into flowering your plant is going to be using very little (if any) N, so I don't think that N lockout is the culprit. Do you use the Bloom and the Bloom Master at the same time? That seems to be an awfully large amount of P, even for blooming. Unless your pH is way out of whack, you do not need to pH organic grows.

If we could get a handle on what exactly your plants do when they go south, it would help us help you.
 
It seems to be a magnesium deficiency...yellowing, with necrotic spots, looks exactly like the pictures online) pH is always right on the money, and I have hard water. Should I be flushing more? Can it be a phosphorus and magnesium deficiency from the hard water/calcium tying it up?

Medium: Black gold
Nutes: Earth Juice Seablast line
Light: Flour--->600 watt hps
Pot: 5 gallon bucket
Feeding: Once a week (water once every 5-7 days as well.) Have used these nutes on 5 grows now..start out small and work my way up on doses. I only give a 1/16th of a teaspoon of bloom master with usually 1/2 tsp of bloom starting at week 5-6. Otherwise, just feed 1/2 tsp of bloom and keep on eye out for black tips.
temps: 60's at night-high 70's during day.
Strain: Purple Diesel, Strawberry Cough
Humidity: average 30%

I know magnesium and calcium have the same charge (2+), and when there is an over abundance of one, the other is not being taken up. (Like pulling into a parking lot when it is full.) If the soil is saturated with Ca, can you still add Epson salts with watering and get the roots to uptake Mag?

I'm thinking a reverse osmosis is the way to go. Does an R/O system affect pH greatly? Any ideas on a good priced unit?
 
your whole issue is too much calcium in your water. That is building up and tying everything up. You can try flushing periodically with distilled water to remove the calcium build up. It seems like it is taking some time for the calcium to build up to toxic levels, so flushing with the same water is only removing the important stuff, while flushing with distilled water and a fflushing agent about the 3-4th week of flower should get you back to low levels and give you time to ffinish the flower beffore it builds up again.

If you have a small grow, then you might be better offf to buy distilled water for the whole grow, but iff you have a good sized grow that will require a lot of water, then the distilled water flush may be the solution for you. :)
 
My tap water pH is 7.5 and there is definitely limescale residue in the hot water kettle in the kitchen, so I assume that some toxins must be building up in the soil.
It goes down to 6.3 after I add the nutes, but when I just water, I have to use pH down to get it into the 6.2-6.5 range.
Are you saying that doing a watering with something like canna flush will correct the soil and let you carry on watering and feeding as normal?
 
from my experience with tap water i find it okay to plant with 240ppm, but i never tested how much calcium there is in it. on the + side, calcium is not present in dissolved solids except as calcium nitrate which makes adding calcium without N difficult. your water already has calcium with no N so you can make use of that
 
from my experience with tap water i find it okay to plant with 240ppm, but i never tested how much calcium there is in it. on the + side, calcium is not present in dissolved solids except as calcium nitrate which makes adding calcium without N difficult. your water already has calcium with no N so you can make use of that

May I ask, if that means the GH FloraMicro Hardwater,,,,has Calcium in it then ? I assumed it was void of all Calcium.
 
May I ask, if that means the GH FloraMicro Hardwater,,,,has Calcium in it then ? I assumed it was void of all Calcium.

i don't know of any particular fert, look at the label, i know that CalMag has calcium nitrate but it is advertised as only calcium and magnesium but eventually you are adding nitrogen too. point is, hydro growers struggle to add calcium without too much N and calcium in source water helps
 
i don't know of any particular fert, look at the label, i know that CalMag has calcium nitrate but it is advertised as only calcium and magnesium but eventually you are adding nitrogen too. point is, hydro growers struggle to add calcium without too much N and calcium in source water helps

I understand your point now :)

I have the opposite problem, to much calcium in the water. I'm switching to the GH because it's supposed to be Calcium free, if not...I'm wasting money :)
 
My tap water is around 250tds, I don't know what is in it but I have to add a little calmag in flowering or I get a deficiency. I recently started using my dehumidifier water which has a tds of nearly 0. As soon as I started using it, overnight I could see the difference, I now have to use CalMag plus every watering but my plants look good.
So if you want near 0 tds water and have a dehumidifier running you can use it or dilute your tap water with it.
 
Thanks for all the replies, I really appreciate it!! I plan on adding cal/mag with every feeding or close to it.
I broke down and bought a $60 aquarium R/O filter. I didn't feel like risking it anymore.

Has anybody experienced their pH dropping after filtering?
 
When you filter water, it will change the pH because the elements combined with the atoms of H2O will give you the total "potential hydrogen" that is pH. It seems like to me that the pH always goes up when there is lower tds in the water but it actually depends on what elements are present. However, the lower your TDS, the easier it is to adjust the pH so if it is way offf in one direction, and has low TDS, it typically doesn't take much to adjust it back to where you want it. :)
 
My tap water is around 250tds, I don't know what is in it but I have to add a little calmag in flowering or I get a deficiency. I recently started using my dehumidifier water which has a tds of nearly 0. As soon as I started using it, overnight I could see the difference, I now have to use CalMag plus every watering but my plants look good.
So if you want near 0 tds water and have a dehumidifier running you can use it or dilute your tap water with it.

dehumidifier is not a good idea, it carries very nasty bacteria that regular disinfecting doesn't help, i strongly advise you to cease using it
 
Zem, I read somewhere it is ok to use, I did clean it good. Other than adding the CalMag everything is the same. I think my plants look better with the dehumidifier water than with the tap water. Thank you Zem, I will keep an eye out for any problems.
 
Zem, I read somewhere it is ok to use, I did clean it good. Other than adding the CalMag everything is the same. I think my plants look better with the dehumidifier water than with the tap water. Thank you Zem, I will keep an eye out for any problems.

I imagine that you would have to clean and sterilize the coils often in order to keep using it safely. I used it on clones for a while and results were disastrous with slime taking over all the stems and damage was irreversible. I read about it too and the conclusion was against using it but maybe with proper sterilization and cleaning it could be used. good luck!
 
Zem, if the water sat for any amount of time I would not use it but my dehumidifier is running constantly right now. I am dumping about three gallons a day out so I thought maybe I could use it. I did bleach the tank but not the coils. I will stop soon, once the water starts to sit I stop using it. I must say tho my clones rooted slower this time around, maybe from the change of water
 
legionaires disease is a bacteria that is commonly found in the coils of air conditioners and dehumidifiers. It is well documented. I would think that you could open it up and spray it down with alcohol to do the initial cleaning, but since air is continuously being pulled through the coils, any pathogens that might be in the air can then attach and grow in the coils. I wouldn't risk it.
 
To late Hushpuppy, my experiment is over. I have stopped using it because the dehumidifier is starting to cycle, so the water is sitting too long. If Legionaires was in the coils I would be dead wouldn't I, I see your concern tho, I also run an in furnace UVC light for purifying my air.
 

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