hard water and epsom salt

my tap water reads 205 ppm @0.5 ec. by all accounts this is considered hard water. in my reading on this site is that hard water is high in calcium. the high amount of calcium locks out magnesium...which ultimately lead to a magnesium deficiency. this is why i come asking for help. everywhere i've read about mag. def. says that epsom salt can be used to reverse the lockout. i'm looking to add epsom salt to EVERY gallon of water, in hopes that the magnesium will balance with the calcium and i won't ultimately have to buy a r/o machine. i went and downloaded my cities water report, but it actually doesn't mention calcium or magnesium at all. only lists amounts of: Barium, Chlorine, Fluoride, Haloacetic Acids [HAAs], Nitrates, TTHMs [Total Trihalomethanes], Total Organic Carbon, Copper and Lead.

so what would be a safe amount of epsom salt to add to every gallon of water?

At 205(acceptable ppm but close to very hard) you will probably need both cal and mag at some point. Use calmag at half strength(2.5 ml per gallon) and you can either add small amounts of epsom every other water/fed(1/2 tsp per gal or less) or large amounts(1-3 tsp per gallon) 3-4 times during the grow.
I have 140ppm tap(considered hard but close to filtered levels). I allow it to sit out not only to get rid of chlorine and other materials but to get it as close to room temp as possible before using.
You do not need a r/o machine for 205 ppm tap.

sorry i forgot that i'm running a 5 gallon dwc, which is why i was wondering about an amount i could add to every gallon, including addback water. just looking to have a more balanced nutrient profile as to avoid lockouts and deficiencies. it seems i get a mag def in flower ~ week 4 no matter what. i honestly rather not have to use calmag, or use as little as possible. using maxigrow in veg and maxibloom in flower, both during transition. honestly constantly plagued with magnesium deficiencies every time

I suppose i could start low and maybe 100 ppm of epsom salt, which if i read was 10% magnesium which would give a 10 ppm increase in magnesium, and go from there. hope a little goes a long way. i'd like to use as little as possible because i noticed it doesn't take much epsom salt to raise the ppm/ec a lot

Nobody else has any input?

I would buy some Magical from Technafloura off of amazon for a few bucks.I have seen some scary salt buildup on epson grow's.

i actually have a bottle of calmag, but it doesn't make a whole lot of sense to add calcium, magnesium, nitrogen and whatever else is in that bottle when all i have symptoms of is a mag def. i know the nutes are in the correct ratios in calmag/magical, but like i said why add 3 or 4 nutrients when only 1 is effing up my grow. I mean i could be just being bullheaded, but i honestly want to LEARN what's wrong and how to fix it, rather than throw a 1-size-fits-all solution at it. from everything i've read, 200 ppm water @0.5 / 0.4 EC (hanna meter) has enough calcium in it to start locking out other nutrients, especially magnesium. i'm not by any means dumb, but this hydro shit is a lot more in depth than most people realize.

I would like to thank those who have responded to my question even though I didn't quite get the answer i was looking for. What i see in most of the advice given for magnesium deficiencies are a fix to the problem, what I am trying to do is prevent these deficiencies by balancing the calcium with magnesium so nothing gets locked out. im really trying to understand this stuff instead of just blindly following advice. every plant I've grown eventually yellows from the bottom up, leaf margins yellow first while the inner leaf area remains green initially, then what look to be dead spots or rust spots on leaves. the plants seem to cannibalize themselves.the stems and petioles turn purple, plant seems to hibernate and then leaves completely yellow and then drop off. plant eventually becomes all stem except for the tops stay greenish. if i increase ec, the leaves tips yellow then burn, if i cut back it gets worse. tried soil, perlite + vermiculite hempy, 100% perlite hempy, hydroton hempy, dwc with hydroton, dwc with perlite.. gh flora series 3 part, tried lucas with m+b only, moved on to maxigrow and maxibloom dwc now... which for all intents and purposes this time the plant looked amazing up till the fourth week of 12/12 and all went to crap again... just when I cracked a smile and thought we were finally getting this. the only real constant has been the water. definitely tried different strains too, not cuts but seeds from attitude. at this point i'm honestly considering to buy a R/O machine, or just throw in the towel and keep buying my meds. I'm open to suggestions

if i remember correctly, the purple petioles show up first.. if that helps. looking on the plant problem thread, it shows like it could definitely be a mag def, but also shows like overall npk deficiency signs too. i'm also points to mag def because through my reading, that seems to be the #1 problem in indoor gardening. but i'm thinking too much calcium because of it would lock out magnesium, and possibly other elements.. i dunno lol. that's why i'm asking for your help, because I don't know.. I'm stoned and i think too much

205 ppm water from one source and 205 ppm water from another source can completely different mineral content. My well water is 280 ppm and 7.8pH and grows just fine with no additional cal or mag. Other than the dolomite and ewc in my medium. And I never adjust pH. You could check with your county health dept and get it tested. Or they may even have test results from your hood on file. This is the best way to know what your water actually contains. A little time here will save you hours of head scratching later....

5 gallon DWC. Refill a 5 gallon bottle at those water stations located everywhere. Fighting hard water by making it harder is foolish science. Read about lockout. Then go buy a refillable bottle and get after it. Even changing your res once a week that is not that much work.

Experienced growers can work with very hard water. I use tap water. But I can read the plants pretty well.

here's my cities water report, i read it but cant seem to find the info i want. doubt it will help... http://www.ci.woonsocket.ri.us/waterconfidence.pdf
b.t.w. i really don't care if people know what city i live in because i'm 100% fully legal, and have 1/12th the amount of flowering plants allowed by r.i. medical marijuana act

are there and water filters that can be bought at a lowes or walmart or home depot that removes calcium specifically? im a little leary of using a filter because i heard some actually add salts to the water to "soften" it

The most important thing you can do with your grow is to make sure your water is clean, get a RO system. Think about it, you spend good money on lights, ballasts, fans and all the other stuff you need to grow but ultimately it starts with the most important thing, water! Get your water's ppm's as low as possible with a good RO system and go from there. Don't get a cheap ass system from home depot or Lowes, go with a 100gpd system from a hydro shop and pay the extra $50, you'll be glad you did. Set it up with a 55 gal rez with a float connected to the water line coming from the to system, when the rez gets full it shuts off, then you will always have fresh CLEAN water. Trust me, its the best money you will will ever spend on your grow! And you can fill your gallon drinking water bottles.

looks like i'm gonna have to bite the bullet, can anyone recommend a decent r/o machine from a respected retailer that also sells replacement membranes. i literally never use more than 5 or 10 g.p.d. but that could significantly change if i can get my shit together and lead a plant past the finish line, instead of pushing and beating it there lol. my smoke is always FIRE, but i just strive for a perfectly healthy plant with THC encrusted goodness oozing off and falling on my main fans... is that too much to ask? seems like the way im growing, leaves little time for trimming because ALL the leaves fall off and the plant looks like little budsicles on long sticks, definitely not high times centerfold material.... that's what i'm after

Those Brita filters can do this all for you and cheaply. Slowly but cheaply.

5 to 10 gallons of RO water needed daily for pot? For how many plants?

Are you growing hyro or soil?

I just ordered this. Very inexpensive and easy to install and it also comes off easy. The filters can be shanged too

http://www.amazon.com/Mighty-Mite-50GPD-DI-Added/dp/B000XDK2IE/ref=sr_1_3?ie=UTF8&qid=1359655824&sr=8-3&keywords=mighty+mite+ro

this is the system i use and on well water at 550ppm starting, after filtering it, its down to 28 ppm. thats removing a lot of shit from my water. http://www.hydrowholesale.com/HYDRO-LOGIC-Hydro-Logic-100-GPD-Stealth-Reverse-Osmosis-System-4305 its filling my 55 gal rez in about a day because i use a pre and post filter, they are the cheap throw away kind for swamp coolers. they help keep the membraine cleaner. i have been on the same filters and membraine for almost a year with no probs. i also use it for filling gallon drinking water jugs.

sorry laptop died. what i was saying is the most i'd use in one day is 5-10 gallons depending on what i'm doing. 5 gallon dwc, and a 3 perlite hempys in veg