Very Hard Water?

OK, so I’m currently using unfiltered, straight from the tap, hard as a motherfucker water.

A few of the values are as follows:

Calcium - 114 mg/l
Magnesium - 8.39 mg/l
Phosphorus - 999 ug/l
Potassium - 11.5 mg/l
Nitrate - 17.9 mg/l

Couple of questions, firstly, how bad is this water for my plant?

And secondly, do I need to supplement cal mag with these levels? Or is this partly why low levels of nutes seem to burn my plant?

I do sit the water for around 48 hours before a feed to get rid of the chlorine, but nothing else.

I May give an RO system some consideration, though I’d rather not, but this partly depends on the replies to this post as I know the water here isn’t good!

What’s the ppms of the water?

Definitely let it sit to evaporate of chlorine. I would put a air stone in there to aid with that.

An RO system is a good investment. I got a 150gpd off eBay for under $100 from purewaterclub. Had it for years then added an extra 150gpd add on for like $70 to make it a 300gpd system. I replace filters every 4 months and it costs <$100 for the replacement membranes. I use around 100gal a week on average

Not sutable for hydro should be fine for soil. Make sure to dechlorinate

Tuckatan said:

OK, so I’m currently using unfiltered, straight from the tap, hard as a motherfucker water.

A few of the values are as follows:

Calcium - 114 mg/l
Magnesium - 8.39 mg/l
Phosphorus - 999 ug/l
Potassium - 11.5 mg/l
Nitrate - 17.9 mg/l

Couple of questions, firstly, how bad is this water for my plant?

And secondly, do I need to supplement cal mag with these levels? Or is this partly why low levels of nutes seem to burn my plant?

I do sit the water for around 48 hours before a feed to get rid of the chlorine, but nothing else.

I May give an RO system some consideration, though I’d rather not, but this partly depends on the replies to this post as I know the water here isn’t good!

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Sure as hell won't be needing any CalMag with that water. I would seriously consider getting an RO unit. You have 50ppm sodium which is not only bad for your plants but not good for those on a sodium reduced diet either tho it's not extremely high. The higher proportion of Ca to Mg will likely lead to Mg lockout so I would supplement with Epsom Salts to up your Mg levels. Tsp/gal with that water always should do it.

With hard water every time you water your plants the salts in it stay behind in the pots so they build up over time and throw everything out of whack. Regular flushing can get rid of the excess but that's a major PITA.

I added up most of the different ppm readings on your water report and got 420. lol Sounds good but it's not. Strange they don't show the total so if you have a ppm pen you should check what come out of your tap. Alkalinity is fairly high and that's what causes problems trying to pH your water properly.

We've been buying RO water for our consumption and for my plants but I'm looking to build my own system. The store bought units come with a 5micron pre-filter. We already filter our dugout water down to 5 so that's no use. The units come with propitiatory filters that cost twice as much as the regular filters. RainFresh, that I use now to filter the dugout water. About the smallest gal/day unit is 50 and I sure as hell don't need 50gal/day.

I've been looking at running our filtered water thru a high capacity 1micron filter -> 0.5micron carbon filter -> 8gal/day RO membrane -> De-ionizing filter -> my 150L storage on a stand with a spigot to fill my 5gal jugs for transport upstairs or the grow room. Safer to pack full jugs up the stairs than down as I've been doing the last 17 years. A 5gal jug hitting the cement floor from 10 ft up means I need a bigger mop! Had to let go of the jug when I tripped once and I've had a few other close calls too.

A note to @Mr.Goodtimes. RO filters work better and last longer if their output more closely matches your needs so doubling your capacity only means your filters need replacing at many less gallons of output than they would if used to capacity. If you only need 100gal/wk then a 16-20gal/day filter would be the most efficient and cheapest one for you. A storage container with a float switch would keep you in lots of water as you need it. The higher capacity just means you can pull the water off in higher volumes as you need it but it's not the best way to go. A filter that can run continuously will give up to 5x as many gallons at the end of it's life than one that makes batches now and again like you are doing now.

My hard water showed 660 Ppm, calcium carbonate builds up on faucets, everything. Don't use it to make coffee, but I cut by 1/3 and add 2/3's to ro water purchased from store, $.35 per gallon.

Thanks for the replies guys.

The PPM from the tap is 447 as of right now, so pretty close @OldMedUser!

The PH is 7.65.

I use some ph down when required to bring it down to around 6.3 as I grow in coco/peat mix not soil.

So I guess all your reccomendations would be to invest in a filtration system? I was kinda hoping I wouldn’t have to, but if it’s needed then I probably should! Though if I can get away with a tap/gal Epsom salts that would be way easier! Lol.

newgrow16 said:

My hard water showed 660 Ppm, calcium carbonate builds up on faucets, everything. Don't use it to make coffee, but I cut by 1/3 and add 2/3's to ro water purchased from store, $.35 per gallon.

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That sounds awesome, I’ll have to check in Tesco, can’t say I’ve ever seen any reverse osmosis water but I know I haven’t been looking! lol.

Tuckatan said:

That sounds awesome, I’ll have to check in Tesco, can’t say I’ve ever seen any reverse osmosis water but I know I haven’t been looking! lol.

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My store has a big "Glacier Water" machine, I get two 5 gallon water bottles filled each time.

I could get de-ionised water, that you use for irons etc, but it’s like £1.50 for 2.5l, I guess I could get a load of that in! Problem solved?

You'd be better off buying an RO filter rather than bottled water. It sounds cheap but that shit adds up. And if you plan to grow more than a few plants, that could be a lot of water to carry around.

I think public water dispenser's can be risky as well. The quality of the water will depend on how well the machine is maintained (changing out the filters and such).

Medicated Bonsai said:

You'd be better off buying an RO filter rather than bottled water. It sounds cheap but that shit adds up. And if you plan to grow more than a few plants, that could be a lot of water to carry around.

I think public water dispenser's can be risky as well. The quality of the water will depend on how well the machine is maintained (changing out the filters and such).

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Yea you’re probably right. Do they come with a tap/hose attachment rather than piercing through the mains pipe? I would end up spending loads on bottled water lol. And look suspicious buying shit loads of de ionised water! Lol

Yes, there are some that connect to a garden hose. The HydroLogic Micro 75 is a 2-stage filter that connects to a garden hose. It's what I use and it was cheap. But, with a PPM of 440, I would invest in a post filter or something, if you go that route. I'm not sure if a 2-stage filter will be enough.

if i'm not mistaken it says conductivity right there on your water report. 798 microsiemens/centimeter. very hard water. can be = 400-550 PPM depending which scale you're using. not sure i'd even want to drink it.

pulpoinspace said:

if i'm not mistaken it says conductivity right there on your water report. 798 microsiemens/centimeter. very hard water. can be = 400-550 PPM depending which scale you're using. not sure i'd even want to drink it.

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I’m not sure I follow! It does say conductivity 798, but I don’t know what it means with regard to drinking it. I’ve drunk it for a lot of years and haven’t been hit by lightening yet

Tuckatan said:

OK, so I’m currently using unfiltered, straight from the tap, hard as a motherfucker water.

A few of the values are as follows:

Calcium - 114 mg/l
Magnesium - 8.39 mg/l
Phosphorus - 999 ug/l
Potassium - 11.5 mg/l
Nitrate - 17.9 mg/l

Couple of questions, firstly, how bad is this water for my plant?

And secondly, do I need to supplement cal mag with these levels? Or is this partly why low levels of nutes seem to burn my plant?

I do sit the water for around 48 hours before a feed to get rid of the chlorine, but nothing else.

I May give an RO system some consideration, though I’d rather not, but this partly depends on the replies to this post as I know the water here isn’t good!

Click to expand...

I’d get an ro system
https://www.homedepot.com/p/APEC-Wa...rinking-Water-Filter-System-ROES-50/206275647
I’ve had this system for a few years works great end up with 0 ppm on the tap side also cross checked with titration and it’s free of hardness and the like and the system is very affordable good luck and happy growing.

Mustangmike said:

I’d get an ro system
https://www.homedepot.com/p/APEC-Wa...rinking-Water-Filter-System-ROES-50/206275647
I’ve had this system for a few years works great end up with 0 ppm on the tap side also cross checked with titration and it’s free of hardness and the like and the system is very affordable good luck and happy growing.

Click to expand...

If you keep up on filter changes with the first stages the membrane filter should last you 2 years ish before you need to replace I’m using mine on straight well water

They can be hooked into almost anything. They mostly use 1/4" or smaller feed line for the typical home units. You can get a screw-in puncture fitting that's easy to install. You just clamp the collar around the pipe and screw the valve in. I have one on my line to feed my dead water distiller. Gotta sell that so I can get the parts for an RO unit.

The borg are back. Haven't seen a mite for over a month and just found a few leaves with spots. Off to do battle again g'damn it!

Hey man, looks like you're getting everything figured out. If you decide to get an RO filter, you should learn about what effects it will have on your plant. Yes, RO water is very clean...but "too" clean can cause complications down the line. People might be able to help you with common deficiencies like Nitrogen, Potassium, and etc, but, the constant use of plain RO water will strip a lot of essential minerals. It may cause deficiencies that are quite rare in most cases, such as Copper deficiencies.

Medicated Bonsai said:

the constant use of plain RO water will strip a lot of essential minerals. It may cause deficiencies that are quite rare in most cases, such as Copper deficiencies.

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I would like to know how RO water strips minerals. Strips them from where? Used for flushing excess minerals from the media it will strip them very well but that's desired when flushing.

If the nutrients used or the soil mix is deficient in minerals like copper then yes you will have that deficiency but it's no fault of the water. The water is just a solvent.

OldMedUser said:

I would like to know how RO water strips minerals. Strips them from where? Used for flushing excess minerals from the media it will strip them very well but that's desired when flushing.

If the nutrients used or the soil mix is deficient in minerals like copper then yes you will have that deficiency but it's no fault of the water. The water is just a solvent.

Click to expand...

https://www.royalqueenseeds.com/blog-reverse-osmosis-water-and-growing-great-cannabis-n410
"The resulting ultra filtered water is stripped of all minerals. You are now responsible for the entire mineral profile of your water before it goes to your precious plants."
"Your nutrient product should be selected with the use of reverse osmosis water in mind. Remember you are now entirely responsible for the mineral content of your water. Organic soil growers will still need to modify their water. Soil is an excellent buffer against ph fluctuations and microbial attacks, but it will not save you from calcium deficiency. At all times, from spray bottle to the final flush stages, the reverse osmosis water will always need to be adjusted."


I'm no expert on this nor do I wish to spark any arguments lol. Maybe my wording was horrible but i'm just going off what i've been told and what i've read on the web.

Also, an interesting article on flushing.
https://zenpype.com/flushing-cannabis-plants-is-a-bad-practice-based-on-flawed-science/