Using Hard Water

Hey there all


I am stressing out about my water in my hydroponic system. I also use Rockwool. Initially I was using water from my water softener. This proved to be a HUGE issue! I had salt lock and my plants turned yellow or wilted and died (not all but a good portion). I then switched to hard water but they do not seem to be doing better (still yellow). When I ask questions the "experts" suggest a RO system or the use of a Tall Boy.

Questions I have are:

What is the difference between using a RO system and the Tall Boy?

Will my plants be ok using hardwater, if so, are there different procedures for using hard water?

What are the best nutrient solutions to use with hard water with the Rockwool?

If you could share your hard water expertise I would appreciate!

No, don't use hard water. Nothing more than 100 ppm. Reverse osmosis water is much better.

Illegal Smile said:

No, don't use hard water. Nothing more than 100 ppm. Reverse osmosis water is much better.

Click to expand...

Many Thanks

purewaterclub.com

Illegal Smile -

Thanks for your wisdom but I have a question:

Should I hook my reverse osmosis up to the hard water supply or to the hard water conditioned supply?
I was told that the ro would remove the salt?

Should I hook my reverse osmosis up to the hard water supply or to the hard water conditioned supply?

Click to expand...

Hook it up to your original source water (ie. hard water supply).

I was told that the ro would remove the salt?

Click to expand...

Yes it will. My source water is from a deep water well, and I end up with water with 8 ppm TDS @ 7.0 PH.

The recomendations of RO manfacturers is if you have hard water (over 250 ppm) first run the water through a water softener and then through the RO filter. Calcium carbonate leaves befind large amounts of CO2 when removed by the RO filter plus the calcium ions are rougher on the RO membrane than the sodium ions. CO2 is what gives the skewed pH readings in RO water as it forms carbonic acid H2CO3. Besides skewing the pH of the water the carbonic acid then is neutralized by carbonates in the nutrient water such as magnesium carbonate etc that then make those chemicals unvailable when they are later needed. The RO filter will very easily remove the Sodium ions and they do not leave precipitaes in the RO membrane housing that would then lower the RO membrane life span and efficiency. Calciun can easily cause those problems.

Here is a great source for RO filters. Always try to buy an RO filter that has full sized cartridge housings and that have all filters mounted vertically but the membrane housing. The top membranes used are the 75 or 100 gpd Dow Filmtec membranes which have a 98% rejection rate. Most of the RO membarnes sold on Ebay use substandard membranes (85% to 95% rejection) and only one carbon filter.
http://www.thefilterguys.biz/ro_di_systems.htm

They use top quality Dow FilmTec RO membranes not the crappy membranes used by the PureWater Club that also use two d cheap sediment filters and only one carbon filter. If you order a RO filter ask that the second carbon filter be a carbon block filter not a coconut filter. Ask that it be a chloroamine filter if your water contains chloroamine. The Filters guys will provide what ever you request. Just send them an email with any questions.

johnblaze1 said:

Hey there all


I am stressing out about my water in my hydroponic system. I also use Rockwool. Initially I was using water from my water softener. This proved to be a HUGE issue! I had salt lock and my plants turned yellow or wilted and died (not all but a good portion). I then switched to hard water but they do not seem to be doing better (still yellow). When I ask questions the "experts" suggest a RO system or the use of a Tall Boy.

Questions I have are:

What is the difference between using a RO system and the Tall Boy?

Will my plants be ok using hardwater, if so, are there different procedures for using hard water?

What are the best nutrient solutions to use with hard water with the Rockwool?

If you could share your hard water expertise I would appreciate!

Click to expand...

R/O wastes ALOT of water. Use it if you don't mind the water waste but might I suggest using a Brita to filter your water.

I tried using hard water but every time I pre mixed some nute solution, the solution would form a crusty layer by the next day. I started to use Brita filtered water and haven't had a problem since and my plants look great.

I do admit it takes a long time to filter water through a Brita. I had to fill my 7.5 gallon reservoir and it took me about 2 hours to filter that much water. Maybe I should buy 2 or 3 more Britas.

Also, a Brita costs considerably less than a R/O system. $20 bucks for the pitcher and a pack of 3 filters costs $20 bucks. Enough to make 120 gallons.

I have hardwater that comes from my well.

Instead of messing with a RO system I use Hardwater Formulated Nutes.

General Hydroponics has a hardwater "micro" formula that I use in conjunction with the regular bloom.

It costs the same as normal "micro" and using it eliminates my need for RO water.

A Tall Boy fitration system is just two filters. A carbon filter and a sediment filter. It will not have any effect on hard water but to remove ant particulates of carbonates present. Most every carbonate will dissolved not particulates. Also with hard water there is usually a large amount of dissolved calcium. The filters will not remove that calcium either.

A brital filter contains Resin beads like a DI filter. However it contains only a small amount as it also contains carbon. It will only remove the carbonates and calcium from a small amount of hrad water before it is exhausted. The are only manafacture rated for around 40 gallons of water with extremely good tap water. About 25% of that with hard water (10 gallons), maybe less.

DI resins are typically used as a finishing filter following other processes such as an RO filter. Thy can provide zero TDS water but have a very limited capacity, measured in grains. An RO filter (home version) does use about 5 gallons of water to produce 1 gallon of RO water but that is still quite a bit cheaper than the water produced by DI resins unless you are willing to recharge your resins. Most people are not willing to do so. An RO filter use prefilters such as the Tall Boy filters (usually smaller in size) then a RO filter. A typical good RO filter will remove 96% of all ions and will do so for thousands of gallons of water. The pay back on an RO versus a Brita is quite quick.

At $8 each for a Brita cartridge, that means from 20 cents to 80 cents per gallon, depending on the degree of your water hardness. At two cents per gallon for tap water and a 5:1 ratio to produce RO water it would cost a maximum of 10 cents per gallon to produce RO water. At say 25 gallons per week. A good RO filter at $150. (56 weeks X 25 gallons/week)= 1400 gallons. A standard set of prefilters will last at least that long. $140 costs + $150 for RO filter = $290 . 1600 gallons / 10 gallons per cartridge X $8 per cartridge = $1280 + $22 for pitcher = $1302 even if your water was good tap water providing greta Brita filter life as advertised (very unlikely) that would mean at best (($1280 /4)+ $22) = $342.

Hard water Micro only addresses the dissolved calcium aspect of hard water by leaving out most of the soluble calcium in regular Micro (1% instead of 5%), it does nothing really to address the carbonates. It does lower the nitrogen by 1%. Lucas formulated with HW micro to a x100 concentrate has as EC of 2.57 and a TDS of 1799, while if formulated with Micro it has a EC of 2.72 and a TDS of 1904. So basically they are just formulating for a tap water with a TDS of 105 ppm with the 25% of the TDS being caused by calcium and they rest by carbohydrates, however they are ignoring the weakening of the over all nutrients caused by the carbohydrates raising of the EC. Water chemistry and therefore nutrient chemistry does not work the way they are pretending it does, but it works well enough for uninformed hobbyists and they make it a hobby not to inform customers. It does however work better than using regular micro with hard water. However if your tap water has a TDS of over 105 ppm then you are definitely lowering the ppm of all nutrients overall by the level of TDS over 105 ppm.

In essence if you have hard tap water I highly suggest you buy an RO filter and run that water through it, not your raw tap water. In all likelyhood you can buy RO water for cheaper than you can produce it with a Brita filter.

Fatman -

Wow! I appreciate your knowledge on the matter, that is EXACTLY what I am looking for. Thank you

When using a RO system are there any other nuances that I should pay attention to, particularly I am asking in terms of nutrients, any help on the matter would help.

I also have hard water just below 200ppm. The GH hard water macro seems to do the trick for me and it is cheaper than all those other things.