Are you measuring the Ec of nutrient mixture as well as Ph?

What is it?

Maybe try 3-part liquid nutrients so you can control NPK ratio to favor growth.

Ph dead neutral is 7.2? Ph 6.5 is more where you want to be in hydro.

I only change nutrient solution every two weeks and have no problem with slow growth.

Given that I don't know what Ec is, and have never heard or seen it mentioned...no!

I didn't want to get too specific with the pH issue, because it's kind of embarrassing. The Grow Juice is color coded. The water is the correct color for hydro. I tested it a couple of times with a kit, as well, and it came out to whatever it was supposed to be. I don't remember the pH...I just assumed neutral. I'll double check, though. Neutral is 7.0.

How big is your set-up? The forum insisted that with only 5 gallons, I had to change the solution at least once every 2 weeks.

The food is growth-oriented. You're supposed to switch when/if you get to the growth stage.

I checked the faq, and I see what ec is...but that's way beyond my means. It seems to me that lots of people do just fine without meters. Am I mistaken? Wouldn't changing the water every two weeks and using the recommended amount of nutrient keep the level right? Or should I not be trusting the commercial nutrients?

I was trying to *save* a little money, as I just got laid off, but as it stands, I may have just grown the world's most expensive 4 tomatoes! :-P

Another thing: when I top off, should I use the same concentration of nutrient per gallon as a new fill-up, or less? My first nutrient solution said less, but the others two haven't mentioned it, and the guy at the hydro store said he's never heard that.

Meters are one of the most expensive items you will be faced with in hydroponics but they are well worth the investment if you are going to stay in the hobby. If you could measure the nutrients and see how much a maturing tomato is using you would understand why changing every 2 week doesn't work well

Art

Find a book on hydroponic growing and read it. I don't have any titles to recommend and perhaps others do.

You're not going to be able to intuit how to do this correctly.

Keep a written record of variables, Ph, Ec, temp, photoperiod, Rh% and etc.

Art, I appreciate your comment, but is it possible that you could simply *tell* me why every two weeks doesn't work well?

I've just become unemployed, and I'm certainly not likely to run out and buy a meter with 75% of my income gone and the mortgage pending. Next year, but right now I'd like to improve what I've got going.

Thank you for your input, Willard, but I've done plenty of reading. I tend to not retain the details of things that I'm not going to use in that form...thus "ec" is filed in "fertility level issues" in my simple mind.

I know it's hard to picture when you're as careful and exacting as you clearly are (and undoubtably with much greater success), but there's a whole sub-catagory of us -mostly silent, out of sheer intimidation - who grow without meters. We're growing to save money, and all those goodies are way too expensive.

I'm not trying to "intuit." I keep track of my variables and attempt to control them. What I'm trying to ascertain here is what variable would cause consistently successful, yet slow growth. My first thought was that the commercial nutrients might be the culprit...I was half-expecting someone to say, "Oh, don't use *that*!" They are, if nothing else, getting too expensive. But I do love that built-in pH tester!

I did receive a potentially helpful message from a member offline, who pointed out that his ec goes up in higher temperatures due to the increased transpiration rate.

He also mentioned that plants have a pretty high tolerance for fluctuation in their nutrient levels, which has been my experience with plants in general.

The thing is, I haven't seen anything even vaguely resembling fertilizer burn, which is what I would expect to see given my relatively high temperatures. On the other hand, I would expect slower growth with lower fertility, but I'd also expect some other sign in the plants.

Since all anyone has mentioned is EC and pH, I assume that it must be a fertility issue, though. No one has jumped on how many cycles or anything else.

Now here's a bit of frustration: I have to start everything over but the the tomatoes, due to my damping off issue (caused by my irritation at the seeds not sprouting because the rock wool kept drying out...I've never had so much trouble!). Anyway, that will put everything else in the growth stage and the tomatoes at the fruit stage in one system under one light. So I suppose I can expect *more* slow growth for that reason as well (I'll be favoring the tomatoes).

I don't mean to flog a dead horse, but the ph is surely responsible for your slow growth. I am another one of those guys that doesn't have much cash to toss at the problem. You could just use a paper test kit, but a better solution may be one of the super cheap meters on ebay. I was able to order both tds and ph meters for around $60. Thats not cheap, but it's better than the $199 combo meter. Hope this helps.

It really does seem logical, doesn't it? But I've tested the pH with the GrowJuice built-in color tester, with a meter, and with a chemical kit. They all come out the same...so I really don't think this could be the problem. I think it's probably the EC issue...too much...too little fertility. Frustrating, though. Anyone out there grow like I do who is willing to admit it?

Does anyone know what Art601 meant by " If you could measure the nutrients and see how much a maturing tomato is using you would understand why changing every 2 week doesn't work well"? Did he mean that I'm changing the nutrient too often? Not often enough? Any clue?

How about a novice response? How is your lighting? Tomatoes need a TON of light, alot more then you might be able to give them in your basement. What kind of lights so you have?

Sorry...thought I'd mentioned that. It's the same 400W MH I've been using all along, in the same sunny room that had the tomatoes growing on the ceiling. As much as there are sunny rooms in Seattle in the winter... It's also not just tomatoes, but herbs and greens, and the growth is consistently slow, for everything, and has been all along. A worthy point, however. Maybe I can borrow a light meter from someone. Probably easier to borrow than an EC meter! It's supposed to be sufficient light for the system, and other plants and seedlings do pretty well in the room. Seedlings in the system don't get leggy...but supposed to and reality are often different, aren't they?

Mkirkwag You might want to change that bulb if it's got over 1200 hrs on it .They will lose alot of there juice after that.They don't last as long as HPS bulbs.MH(more blue spectrum)your plants will be more stocky compared to a slightly leggy HPS(red spectrum)but it's not that bad and the cost in the long run is much better with hps and your plants will benefit when they produce flower or fruit.That is where red spectrum is more benefical to a plant.Hence mh for veg and hps to flower but hps ok all the way like I said.My 2 1/2 Jungle Fever(O).

Yeah...I thought of that, and if it hadn't been a problem from the start, I would have assumed that a dying bulb was the answer. I chose MH because I grow mostly veg. Didn't know hps was more economical. Don't think my fixture will handle hps, or I'd switch...maybe. I'm seeing mh in Lowe's for not too much. Funny about that...the mh lamps at Lowe's have radiation warnings, and say not to work in a room with them! I'm in that room all the time. I've never seen that before.

Yea mkirkwag the hps's give off more lumens(Ithink) than mh bulbs and what I meant also was that hps's last so much longer as a economical choice o.k and no you can't use a hps bulb to your mh ballast it doesn 't work that way.Now about your system I have no idea but if I'm not mistaken shouldn't your tomatoe ph soulution be ph'd at 5-5.5 .for max. uptake in the medium because then you'd have uptake of the plant at 6.(See I think that way because if your medium starts at 7 which most of the mixes do then you'd want to tweak your solution fert mix to 5-5.5 to contrdict the ph of 7 to mix down to 6 right at tomaters ideal ph hence happy tomater)Am I wrong here or am I thinkin right?I to am just a rookie I just grow a variety of house plants in pottin mix that I rule at.I think.(lol)Jungle Fever(O).P.S What is the temp of your solution anyhow?

I dunno, jungle. Tomatoes in soil like anything from 5.8-7.5, but I believe their preference is 6.2-6.8...that's what I've read, anyway. I just stick 'em in and they grow. I suppose they would like the same in hydro. I finally looked at my Grow Juice - the pH is somewhere btwn 6.0 and 6.7 (it's a color code)...I'm guessing it's nearer to 6.0, given how pale the color is. That's how the color based pH testers work for aquaria, anyway.

Don't know the temp. The room is about 78 in the day and in the mid 60s at night. Used to do it in a much cooler room and blamed the slow growth on that! :-P

I think Willard is right. I'm going to have to give up the whole business until I can beg, borrow or steal...or gods of lotto forbid, *buy* an EC meter. I just went in and tasted the new batch of basil...YEACH!!!! nasty, bitter....green beans are tough, the dill doesn't have much flavor and the tomatoes are tough and a little too acidic with a thick skin (could be the variety).

I should also switch to three part...I never get around to switching to bloom juice for my tomatoes. No impact on the greens, but certainly on the maters and beans.

I know this is an old post, but if you have or know someone with an electronics background, here is a related post on home EC meters.

http://forums.gardenweb.com/forums/load/hydro/msg0119561418537.html

If you ever read any information about home EC meters using ohmmeters they will not work. As it was explained to me EC meters require alternating current, whereas an ohmmeter uses direct current.

Glad you told me that last part!

Never too late for good info.

I was thinking of trying again outdoors, if I can think how to convert the plug to safe-for-outdoors.

Sorry, I've been away. If you're still having problems, here's my 2 cents.

PH is very important, but I don't use a meter. I just buy the cheap (about 6 bucks) PH solution with test bottle. I adjust + or - to get the test solution to look a pale green. It works very well.

Next your damp off problem. Are the plants setting in water too long? Are you feeding too often? Is the temperature going low at night? Too much moisture in the air? Are you having some kind of mechanical failure? A dehumidifier might be one solution if too much moisture in the air is the problem. That's spendy though and your problem could probably be solved by looking more closely at your equipment, water level and the plants roots to find out what is going wrong.

Next, I agree about checking your lighting source to correct slow growth. I change my bulbs once a year.

Finally, this is a very small system, didn't you say 6 gallons? How much total water have you replaced by topping off before you do a complete water change? I'm guessing these plants aren't getting adequate nutrients. If you've replaced half the water then the nutrient solution is probably too dilute for optimal growth.

I wish you luck.

Thanks!

I already know the pH - there's a tester built into the nutrient.

I only had damping off once, and I knew the cause of that -- my impatience and annoyance with having set up too few cycles - I overreacted and set up too *many* cycles. That, and no fan.

I'm sure you're right that it's either a light or a nutrient issue.

You're probably right that the light needs changing, but the fact that the tomatoes do well and the nothing else does suggests to me that the light is a secondary issue. Tomatoes are light hogs, after all.

I originally used the company's topping off schedule, which could be the problem. Topping off by schedule doesn't allow for the differences in evaporation in different circumstances. Now I top off to keep the water level up. I'm sure that by the third top-off--what used to be Week Three--I've often replaced half, as you noted. Top off four--what used to be Week Four-- is no nutrients...although I usually only run 24-48 hours with no nutrients. This last round I topped off regularly and changed the solution every two weeks. Art601 said something cryptic about why changing out every two weeks is a bad thing, but never clarified.

So what do you suggest? Top off with nutrient water so there's never a dilute solution? Then just run clear water for a day or two once a month? (I have actually done that, but I may not have had my other factors in order at the time.)

snip
So what do you suggest? Top off with nutrient water so there's never a dilute solution? Then just run clear water for a day or two once a month? (I have actually done that, but I may not have had my other factors in order at the time.)
snip

How would you recognize a dilute solution if you don't measure the Ec?

The instructions you have from the nutrient manufacturer are way to general for any particular garden. Do they know the percentage of tomatos you are growing?

Different plants take up differing amounts of nutrient at different growth stages and no general printed nutrient regimen will cover this.

Get an Ec meter and measure the solution strength...............

I completely believed you that I need an EC meter, Willard3. I'm not ignoring you. I guess I forgot to mention that I'll do that as soon as I can, but unemployment doesn't run to buying new toys, however useful they may be. It does, however, encourage one to try to create food out of what's at hand, thus the continuation of the our discussion beyond that point. Interestingly, I've been growing exactly the same proportion of tomatoes to greens that the manufacturer uses for an example. I agree, however, that the nutrient level is the most likely problem, probably exacerbated by the old light bulb. I also agree with you that it would be better and more economical to use a 3 part nutrient, and I will, once I've used what I have. In the meantime, I'll just have to keep searching and taking advice on the best way to muddle through until such time as I can get my hands on an EC meter. Mystyraine seemed to have an idea about the best way to approach that.

Try this site and recipie for success.

This doesn't require an Ec meter and they say it works.

Of course, they sell nutrients...........

Here is a link that might be useful: BC Hydro

"Of course, they sell nutrients..........."

LOL!