Local (tap) water quality and its contents for DWC

Niblixdark

Well-Known Member
All tap water is different, am lucky enough though to not need a RO unit. I can get away with not needing that much extra cal mag fortunately.

Cal-mag is good if you have fungas knats as they can cause deficiency in these two elements. But also sometimes needed in the first weeks of flowering as they are in high demand from the plant ussualy.
 

Prismo

Well-Known Member
All tap water is different, am lucky enough though to not need a RO unit. I can get away with not needing that much extra cal mag fortunately.

Cal-mag is good if you have fungas knats as they can cause deficiency in these two elements. But also sometimes needed in the first weeks of flowering as they are in high demand from the plant ussualy.
I see. What abour your tap water? Is it soft? And how many ppm does it have?
 

Prismo

Well-Known Member
My city tap is between 80 and 120 ppm. Great Lakes water.
That sounds very good indeed.
My tap water has about 180-190 ppm. Do you think I should use it as it is? I could wait a few more weeks and get a low priced yet seemingly worthwhile RO installation. My plan with that would be to dilute it with my tap water in a 50/50 ratio, which would net me slightly below 100 ppm. As I said somewhere here earlier I don't trust myself using only RO water yet so the dilution plan sounds pretty good right now. But I really wouldn't want to invest the extra money right now if I don't REALLY have to. On the other hand, I don't want to just use my high ppm tap water and possibly have to deal with a result that could have been avoided, like a comparatively low yield and such.
What do you think?
 

ThaMagnificent

Well-Known Member
or give dwc a shot with your tap water. they do make a hard water version of GH flora micro.

i just like RO water because it eliminates your water as a potential problem.
This was my issue. My tap is pretty good. Around 220 ppm but the bigger issue is the alkalinity of the water so my pH would jump up sometimes a full 2points every 12 hours because tap water is buffered to be around 7 pH
 

Prismo

Well-Known Member
This was my issue. My tap is pretty good. Around 220 ppm but the bigger issue is the alkalinity of the water so my pH would jump up sometimes a full 2points every 12 hours because tap water is buffered to be around 7 pH
What exactly is this "buffering"? My tap water has a pH of about 7,9, but I don't have conclusive data if it does those big jumps, too. Should prob do such a measurement right now and leave a bucket of ~20°C water out for the night and measure in 12 hour cycles or something...
 

Niblixdark

Well-Known Member
That sounds very good indeed.
My tap water has about 180-190 ppm. Do you think I should use it as it is? I could wait a few more weeks and get a low priced yet seemingly worthwhile RO installation. My plan with that would be to dilute it with my tap water in a 50/50 ratio, which would net me slightly below 100 ppm. As I said somewhere here earlier I don't trust myself using only RO water yet so the dilution plan sounds pretty good right now. But I really wouldn't want to invest the extra money right now if I don't REALLY have to. On the other hand, I don't want to just use my high ppm tap water and possibly have to deal with a result that could have been avoided, like a comparatively low yield and such.
What do you think?
Check this link out

https://www.rollitup.org/t/high-ppm-tap-water.385800/

And

http://www.growweedeasy.com/ppm
 

Niblixdark

Well-Known Member
Thanks, mate. Checking it out right now.
I would recommend using any type of water filter other then RO to "reduce" PPM and save on the RO unit and extra supplements needed for RO.

My water may be low PPM and all but it has allot of chlorine in it and it fizzes away for 24 hours. It likes to burn the plants a bit if its freshly out of the tap.
 

Prismo

Well-Known Member
I would recommend using any type of water filter other then RO to "reduce" PPM and save on the RO unit and extra supplements needed for RO.

My water may be low PPM and all but it has allot of chlorine in it and it fizzes away for 24 hours. It likes to burn the plants a bit if its freshly out of the tap.
I guess due to the involved costs I'll just go with plain tap water for now until I can upgrade or add to my equipment.

I live in an averagely big city (population >500k) and the water here is just treated groundwater that has its iron and manganese content removed in the process (traces left). Surprisingly, it doesn't contain any chlorine, just chloride, which is probably one of the main perpetrators for the ppm (34 mg/l which equals 34 ppm if I'm not mistaken; with the allowed maximum here being 250 mg/l).
For the nutes, I'll have to start low anyway since I don't know what the breed I have prefers (Sweet Afghani Delicious fem.) and work my way up.
 

Niblixdark

Well-Known Member
I guess due to the involved costs I'll just go with plain tap water for now until I can upgrade or add to my equipment.

I live in an averagely big city (population >500k) and the water here is just treated groundwater that has its iron and manganese content removed in the process (traces left). Surprisingly, it doesn't contain any chlorine, just chloride, which is probably one of the main perpetrators for the ppm (34 mg/l which equals 34 ppm if I'm not mistaken; with the allowed maximum here being 250 mg/l).
For the nutes, I'll have to start low anyway since I don't know what the breed I have prefers (Sweet Afghani Delicious fem.) and work my way up.
Good luck Prismo, You'll figure it out !
 
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FennarioMike

Well-Known Member
I always heard soft water and sodium were bad for plants. I never tried it though. Make sure to let us know how it works out.
Water that has been softened by a water softener is bad because the softener exchanged ca/mg ions for sodium 1:1, so you end up with soft water that's high in sodium.

Soft water out of the tap is fine as long as you supplement with ca/mg
 

Niblixdark

Well-Known Member
Water that has been softened by a water softener is bad because the softener exchanged ca/mg ions for sodium 1:1, so you end up with soft water that's high in sodium.

Soft water out of the tap is fine as long as you supplement with ca/mg
They do make a 3 part GH for both soft water and hard water.

Be aware that city sewer and road pipe ect construction repairs can alter the PPM in tap water during summer fall.
 

Prismo

Well-Known Member
Water that has been softened by a water softener is bad because the softener exchanged ca/mg ions for sodium 1:1, so you end up with soft water that's high in sodium.

Soft water out of the tap is fine as long as you supplement with ca/mg
I see. If I researched correctly, another district of the city I live in is treated with sodium hydroxide more often than the other ones. Even with a lower pH than mine, it still contains more sodium. What you stated is probably the reason for that, since it's written that the water in the district I live in is treated with calcium hydroxide more often than sodium.

Yet still, 18 mg/l shouldn't be "too high", right?
Can you give info about the other values, too? Calcium is 49 mg/l and Magnesium is 5,6 mg/l. I have CalMag ready btw.
 

FennarioMike

Well-Known Member
In my opinion all of your other water chemistry is fine. I used RO water for a long time, and after adding ca/mg the PPM (700 scale) would go from 0 to 400 or so. My water is normal hardness with a ppm of about 300 (again, 700 scale). Now I use tap water and supplement ca/mg 1/4 strength and everything is just as happy and I'm using 1/2 the water and 3/4 less ca/mg.

You could do the same. Since your water is soft, I'd go with maybe 1/2 strength ca/mg to supplement. Before you mix anything in the water, let it sit out for 24 hours or use an air stone to bubble air through for a couple of hours to off gas chlorine and you should be good to go. Your water's PPM says 380 ms/cm which is 500 scale which equates to about 420 on the 700 scale. That's a bit high, and it would go up to about 600 just after adding ca/mg. So you may want to dilute your tap water by 1/3 with distilled or RO first.
 

FennarioMike

Well-Known Member
They do make a 3 part GH for both soft water and hard water.

Be aware that city sewer and road pipe ect construction repairs can alter the PPM in tap water during summer fall.
Yep - you're absolutely correct. It's always a very good idea to measure the ppm of your starting water, then after each addition of your supplements and nute mix and write them all down as you do it. This way you'll know which component is contributing what to your overall PPM, you'll catch any incoming water ppm spikes, and if you forget what you added last, your PPM reading will be an indicator.
 

EveryBlueMoon

Active Member
I run DWC with the the GH Trio, Hydroguard, floraliciuos plus, and liquid Koolbloom during flower only. You don't "need" anything beyond the trio, but the additives seem to boost my yield. And cal mag as needed
Hey bro I'm doing DWC for my first time. I've done EBB & FLOW for ever but decided to give it a go since I sold my ebb and flow set years ago. I've already made the DWC buckets but I want to know if I can use AZOS instead of Hydroguard. The only reason I ask is because I already have the AZOS... but I don't wanna mess it up cuz I didnt wanna spend 20 bucks... anyways your time is much appreciated, and thank you in advance.
 

Prismo

Well-Known Member
In my opinion all of your other water chemistry is fine. I used RO water for a long time, and after adding ca/mg the PPM (700 scale) would go from 0 to 400 or so. My water is normal hardness with a ppm of about 300 (again, 700 scale). Now I use tap water and supplement ca/mg 1/4 strength and everything is just as happy and I'm using 1/2 the water and 3/4 less ca/mg.

You could do the same. Since your water is soft, I'd go with maybe 1/2 strength ca/mg to supplement. Before you mix anything in the water, let it sit out for 24 hours or use an air stone to bubble air through for a couple of hours to off gas chlorine and you should be good to go. Your water's PPM says 380 ms/cm which is 500 scale which equates to about 420 on the 700 scale. That's a bit high, and it would go up to about 600 just after adding ca/mg. So you may want to dilute your tap water by 1/3 with distilled or RO first.
Good to hear that it appears to be fine, but I'll prob start with 1/4 CalMag, too, and only if deficiencies occur.
Somewhere in this thread I wrote that I tested my water. It has about 180-190 ppm at about 20°C, but what exactly are those scales you speak of? Never heard of it before. Nevertheless, someone already recommended to dilute my water, but I really don't want to go through the struggle of buying and having to transport all those gallons. I'm short on finances and very lazy. Add to that the fact that you need to switch out the entire reservoir every 7-10 days which makes it even more of a struggle tbh. I really would like to just start like this. Also, I heard about people that used tap water with a way higher ppm than mine and they were absolutely fine.

By the way, luckily, my water doesn't contain any chlorine, only chloride. So the 24 hour sitting period is most likely not even neccessary and it's good to use right out of the tap.
 

Ryry94

Well-Known Member
Hey bro I'm doing DWC for my first time. I've done EBB & FLOW for ever but decided to give it a go since I sold my ebb and flow set years ago. I've already made the DWC buckets but I want to know if I can use AZOS instead of Hydroguard. The only reason I ask is because I already have the AZOS... but I don't wanna mess it up cuz I didnt wanna spend 20 bucks... anyways your time is much appreciated, and thank you in advance.
Sorry bud, I've never used Azos so I can't give you an educated answer. I looked at the Azo's website and they don't mention use on hydro, but they show lots of photos of roots in a cloner, which is a hydro system for sure. Sorry can't give you a solid answer.
 
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