I'm not looking to buy a pH/EC meter with no clue on how to use it. That is the reason for this post; not only to find out how to use the meter, but whether it's even necessary. Perhaps I don't need it, or perhaps I simply need something that reads pH. My intent is to maintain optimum levels so my plants grow in a healthy environment. I'm adding liquid lime to supply calcium and magnesium for my chiles and tomatoes, which also affects pH over time. I'm also unsure how much fertilizer to add, when to add it, how much to dilute it with, and so on. The instructions on my fertilizer say to mix it with gallons of water at a time. I've noticed that the solution can get quite stinky if mixed in large amounts, so I opt for mixing it in smaller, useable amounts. I was hoping that having such a meter that measure pH and nutrient ppm/ec would help make things easier for me. Also, I only have a couple plants which I grow indoors, but I want them to be the best they can be.

I am not assuming anything from that "famous 300 ppm" anymore, until I've seen a complete analyses ;-) Did you go wrong somewhere? Perhaps, - all depends on what you were referring to. As calcium chloride (at least as it is commonly used) is a chemical compound that has either been produced from limestone or is a byproduct from other chemical manufacturing - it has to be seen and treated as a chemical product. Products come in different grades and purity (purity of CaCl is ranging from approximatively 70-96%). That is why its ACTUAL content in (ppm of) elements can't be calculated by its molecular weight only. The calcium chloride I was referring to is commonly used food grade-, but has only a elemental purity of 75%. Hence, simply take 75% of the molecular weight of the component, and you've got the ACTUAL 127 ppm of chloride and the 72 ppm of calcium contained in that particular (one has to add) calcium chloride. Actually it is the data from the CaCl I always use when composing and calculating my nutrient formulas. Does calcium chloride look like a good source of calcium to me too? Firstly: chlorine for instance is an essential micro nutrient in plant nutrition and is supposed to aid root growth. Still, the average in soils (top part) is only about 10 ppm. Example: I'm only using calcium chloride as small part of my formulas, and only as long as I can limit the TOTAL chlorine content in a nutrient solution to a maximum of 60-70 ppm. I'm using just enough CaCl to provide around 40 ppm of Ca , which obviously brings these some 70 ppm of chlorine to the formula. That's enough to complement the Ca provided bay another component called calcium nitrate. Indeed CaCl (when sparingly used) is actually a particular useful additive when composing formulas that require relatively low nitrogen- in relation to normal or high calcium content. Otherwise, with such formula it's not possible to supply enough calcium through calcium nitrate only, without exceeding your N-target. But in case some tap water already has high chlorine content, - this component is obviously NOT suited as such an additive and no good source of Ca, not even to complement some calcium in a particular case. Best is always to have pure water with lowest mineral or saline (=low ppm) content possible, - and there you go with any formula and any suited ingredients you want.

EC, PPM, pH meters Posted topics included in this FAQ are: Basics of EC PPM testing--is it necessary? Looking for a nutrient meter Basics of EC Posted by thedude27 (My Page) on Thu, Jan 12, 06 at 16:46 Hello, I'm new to hydroponics growing and have a basic question about mixing the nutrient solution. Currently I'm growing some sage in a homemade DWC system and was wondering if I'm mixing the nutrient solution correctly. When you are mixing to obtain say 1500ppm nutrient solution do you add the 1500ppm on top of the reading of your water without solution? So if I had water that was reading say 500ppm before adding anything would I then add solution to bring the reading to 2000ppm? Or could that provide your plant too much of a certain nutrient (obviously something is in there raising the count). Also at what point (well water) hardness would you consider using distilled/spring water? For me its not such a big deal since my grow (crop) is small for now, but it would be easier to just use tap water (or filtered tap water). Response: Posted by: hank_mili Z11 (My Page) on Fri, Jan 13, 06 at 17:40 The PPM in your tap water is the same whether you have a tablespoon or a gallon. The PPM of the solution from the nutrient concentrate will depend on the volume of water you mix with it. Need to keep in mind that PPM is always a calculated value not like EC (electrical conductivity) which is directly measured. This is why many prefer using an EC meter for measuring nutrient concentration versus a TDS (total dissolved solids) meter, which is an EC meter with a calculation algorithm built in. Unless otherwise stated on the label, the calculated PPM of the solution will assume mixing pure water with the concentrate. But to answer your question the final PPM will be additive and 2000 PPM would be correct. Posted by: thedude27 (My Page) on Sat, Jan 14, 06 at 23:29 Thanks a bunch Hank, that helped a lot :) I guess I should have gotten the EC meter instead of the PPM but I got a really good deal on a Newport DSPH-3 (dissolved solids/PH) that I couldn't pass up. Although I'd imagine I could just get the conversion formula from the company and reverse the calculation (although I suppose I'd need accurate temperature readings too). Thanks again PPM testing--is it necessary? Posted by Luckyleaf 7 TN (My Page) on Sun, Oct 10, 04 at 23:22 Is it necessary to use PPM testing if I will be growing some tomatoes in a bubbler? Also, if you say it is, what should the ranges be for the nutes in the veg stage and the fruit stage? Thanks! Response: Posted by: AdrianaG AL z7 (My Page) on Thu, Oct 14, 04 at 19:09 Only if you want healthy plants...and the meter you want is an EC meter, not a ppm meter. Posted by: hank_mili Z11 (My Page) on Sat, Oct 16, 04 at 2:53 Checking your pH and salts concentration of your nutrients is analogous to checking the fluids in your car. You can get away with not doing it but it is not recommended. It's extra work and expense but gives you important information on the condition of your nutrients. Product.....pH..............cF...........ppm Tomato....6.0 - 6.5...20 - 50......1400 - 3500 Posted by: Luckyleaf 7 TN (My Page) on Sat, Oct 16, 04 at 11:17 How do I get the PPM up to 1400-3500? Just add 2x the recommended dose of the nutes for the plants? The PPM of my water is ~50, so thats a far way to go Posted by: willard3 (My Page) on Sun, Oct 17, 04 at 9:58 It will make a difference how large your reservoir is to get nutrients up to correct ppm. Start keeping a log and how much and when to add and change nutrients will become much clearer to you. PPM and Ph are closely related so you should test and record Ph as well. Posted by: Luckyleaf 7 TN (My Page) on Sun, Oct 17, 04 at 15:49 Well I'm doing 5 gal bubblers, and I wont have a reservoir. It is usually like a tsp or something per gallon for each nute, but since tomatoes have different needs I would have to do something like a tbsp per gal? ...in general I would have to use more than the recommended dose Posted by: willard3 (My Page) on Mon, Oct 18, 04 at 8:49 All nutrients are different; all nutrients have different mineral concentrations. 1. Go buy an EC meter 2. add nutrients 3. Measure nutrient concentration Posted by: Hydro4me z5 IN (My Page) on Tue, Oct 19, 04 at 11:37 Hey there Adriana, I have the (brand name) Nutrient Meter, but it reads, "442", "KCL", and "uS" (which I believe is micro siemens). I have heard that the 442 is good for testing pond water with fish and plants, and KCL is potassium chloride. I have no clue which one to use for testing my Millennium nutrients. I try to keep the blinking LED's in the middle, but peppers or tomatoes require higher levels. Any advice from other hydro gardeners? Thanks, Jason Posted by: willard3 (My Page) on Wed, Oct 20, 04 at 21:25 Most published stuff on hydro is given in ppm. I have on that has been working fine for 5 yrs. RE: meters ppm (ec) and ph Posted by: NLG1 7b-8a (My Page) on Wed, Apr 27, 05 at 18:11 You can find meters for around $30.00. They work, but for how long is the real question. What you want out of a meter. 1: waterproof 2: warranty 3: replaceable probe 4: pH range 1-14 +/- .1 5: ppm range 1-1999 Posted by: willard3 (My Page) on Thu, Apr 28, 05 at 9:20 A good cheap meter is an oxymoron. You should get a good meter, no matter what it costs. Hydro goes sooooo much better if you know accurately and repeatable the Ph and EC of nutrient solution. $50/meter is what I paid and it's worth every penny. Posted by: HydroBotany Indoors (My Page) on Fri, Oct 28, 05 at 18:40 (HydroBotany suggests a double junction (DJ) product). That is the most important thing with hydroponics. A DJ meter handles the environment the best and last the longest. artisan also has a good meter and it can be used continuously if you want it to RE: meters ppm(ec) and ph Posted by: hank_mili Z11 (My Page) on Fri, Oct 28, 05 at 21:49 I tend to be biased toward (another product). Very reliable. No problems so far. RE: Looking for a nutrient meter Posted by marshallwilson z4 CO (My Page) on Sun, Sep 25, 05 at 9:27 New to hydroponics. Basic ebb and flow system. Using 2 part dry nutrients (from CK). Currently outside, will be moving inside under lights soon. I'm looking for an inexpensive way to monitor my nutrient level. Hoping for suggestions on meters. As an alternative; can I just change out the entire solution every 2 weeks (suggestion from the local hydro shop)? I do get a fair amount of evaporation during the 2 week cycle. Should I just top off the nut solution with plain water? Thanks Marshall Response: Posted by: propman Z10 CA (My Page) on Sun, Sep 25, 05 at 11:47 I just got a ppm meter for about $35. Before that I just used the recommended dose on the bottle per gallon of water. What I found when I tested the water was way too stong because my water has 150 ppm before I added nutrients. The meter is a good idea. Here is a link that might be useful: pictures of my lettuce Posted by: hank_mili Z11 (My Page) on Sat, Oct 22, 05 at 1:03 Hope you have a pH meter or strips. One can calculate ppm but you can only measure pH. RE: Looking for a nutrient meter Posted by: HydroBotany Indoors (My Page) on Fri, Oct 28, 05 at 18:03 Just top it off with plain water.

you want to reach the PPM or EC specified. the maker of my nutrients specifies 1800ppm for adult plants and 1400 for seedlings. I run the adult plants at about 1600ppm. and I only check it about once every 2 weeks. the larger reservoir you have, the less often you'll have to check and adjust it. you'll want to keep it up where they specify, but I've gone on long vacations and when I got back the PPM was around 300 and the plants seemed fine. they won't grow as fast, but as long as they keep getting water they should be ok.