Question and Answer Page 3


(from home depot) tomato plants what size PVC pipe is good for tomatoes
head or iceberg lettuce in hydroponics What is ppm and TDS?
9 plant hydro garden Suggestions for a good book
question about nutrient solution raise PH they suggest to add Asprin.
Earth Juice? hydroponic gardening is easy
rockwool or gravel developing leaf and stem curl.
size pump with the 11 plant system What kind of paint is best for bottles
cannot find any hydroponic fertilizer  

hi,can I use commercial (from home depot) tomato plants...in an ebb and flow system? I wondered if I soaked off the soil/peat that comes in the flats if I could then stick em in my perlite/vermiculite mix?..or is it safer to cut them up and clone them..Its rather late to start all the way from seed.

Yes you can. That is the way I do it.  Because bedding plants are so cheep I don't bother cloning tomato plants.

Could someone please tell me why head or iceberg lettuce is not able to grow properly using hydroponics. regards
Rudy Klein.B.Sc..

Re: Iceberg lettuce:
I am sure that iceberg lettuce will grow very well in hydroponic gardens. I have seen beautiful head cabbage in rockwool drip and NFT systems. They both have about the same nutrient requirements. I am going to try a couple of iceberg plants and see what happens. I think the main reason that commercial growers grow varieties of leaf lettuce and not head-type is that leaf lettuce develops faster and they can harvest more crops per year. Anyhow, I'll give iceberg a go and post pictures of the development - or non-development - which ever way it works out!
Ron K.

Eric Wrote: We put together a hydro unit several weeks ago using 4” PVC pipes 5’ long with small gravel. The unit is at the back of the property and I didn't want to run AC wiring through the back yard. We have utilized a 12 volt motorcycle battery, bilge pump w/ float switch shutoff, a small solar panes to recharge the battery.
How about a Water switch?
Look at http://www.mnsinc.com/ham4fun/waterswitch.html
If you have more time than money, you can come up with all sorts of things to play with. Ed

Fellow Hydro's, I've just assembled a basic 9 plant hydro garden (The one with the upside down 2litre bottles cut in half). My question is how do I arrange everything in the upturned 2 litter bottles?
How do I use solo cups? How do I place the young plants in the 2 litter bottles? All help will be
greatly appreciated, Bart.

Hi Bart
You can arrange the pvc grid/bottles anyway you like as long as they are the same height and you have an intake for the pump and an overflow to control the height of the water.
The solo cups with holes in them sit in the bottles to make the plants removable so you can clean your garden.
You can then take bedding plants or any size plant that you think the roots will fit in the solo cup after you have washed the dirt off or other growing medium from the plant roots.
You can even take some plants (especially herbs and spices) and cut the plant into a few plants and
then place them in the solo cups. That's the fast method to fill your garden.

Hi, I am new to Hydroponics and I have a question about nutrient solution.
Presently I am using Earth-juice Grow. I intend to use EJ-Bloom too but I haven't had my system for that long.
The NPK ratings are extremely low on these (2-0-1) and (0-3-1).
I have noticed that some chemical nutrients and even other organic nutrients have much higher ratings.
Can anyone tell me a comfortable level that I should experiment with.
Also, will doubling the amount of concentrate that I mix with water effectively double the right nutrients or will it raise some micronutrient to a lethal level?
Thanks so much. Ben Conley

Hi Ben
The nutrient I use (Formula One A & B) is 7-0-5 and 1-6-6 so I wouldn't worry to much about those numbers as long as it's formulated for hydroponics and not for dirt.
By adding more nutrient solution it will raise the N-P-K in equal amounts..
If you suspect that your nutrient solution is way off I would dump it and mix up a new batch.

Hello My question has to do with what I assume is a disease, I do not know the specific name but it is a root rot. I have check with my local hydro store and their only answer was to cut every thing down and start again. I am sure the cause was light exposure to the roots. I use a 400w hps. Are there any other answers? Please help!

Hello Everyone...
I grow tomatoes, peppers, and cucumbers outside in gutters, using rockwool cubes and a pump operating 24 hours a day. I was beginning to see the plants get stressed looking with the daytime temperatures approaching 90f on a daily basis. I backed down my nutrient level to about 800-900 ppm and they have recovered and are now thriving.
Is this due to the fact that the higher the nutrient temp <around 80f>, the less oxygen it can hold... or something like that?

Hello All, Looking for extensive background and experimental information on hydroponics. All information involving hydroponics using the plant basil and a variety of growth medians would be appreciated. Experimental results a big plus. All information is welcome. Thank- you.

Earth Juice
Anybody ever try a nutrient solution called Earth Juice? Its supposed to be 100% organic. Just
wanted to hear from anyone who has used this type of nutrient solution.

Earth Juice is a very good formula for organic hydro. organic will always have lower numbers compared to chemicals due the easier absorption rate. DO NOT double the nutrient level, are you having any troubles with deficiencies? if you are then I would recommend adding an amendment that corresponds to the nutrient rather than overdosing with a complete formula, ie:
K= bat guano, blood meal P= earth worm castings N= bone meal, urine(1/3 per gallon of water, sounds gross but its better than any commercial fertilizer in absorption especially in a high pH situation) any micro or minor nutrient can be effectively supplemented by using kelp or seaweed(can be bought at any good nursery)

I'm setting up a small ebb and flow system and am trying to decide between using rockwool or
...anyone have any opinions on which one would be better to use. Thanx.

I like grow rocks because they are reusable and rockwool is a mess to dispose of.   And any growing medium that I have to ware gloves and a mask to work with I don't want nothing to do with.
You have to keep thinking recycle - recycle - recycle!

What size pump do I need with the 11 plant system that is described on this web page? It uses 1/2"PVC pipe that is raised table top high above the tank. Also is there a problem of the first few plants getting "washed away" and the furthest away getting almost none of the nutrients?

The smallest you can find will work. 70 GPH to 120 GPH

ok, I have finished building my system.
I found an outdoor timer at Fred Myers with 24 possible settings for $33.00 (Alaska prices)
However, due to my remote location, cannot find any hydroponic fertilizer.
What I did find was a water soluble organic (fish emulsion) fertilizer. My question is will it work? It's rated 5-1-1 .05% from ammoniac nitrogen .75% from water insoluble nitrogen 3.75% other water soluble nitrogen 1.0% phosphoric acid 4.0% chlorine Note: primary nutrients derived from sea going fish I'm thinking of starting will tomatoes. Will this work?
We currently are having about 20hrs sunlight up here in Fairbanks Alaska can I keep the feedings
round the clock under those conditions (Temp range 45-70) I'll be growing the in a green house.

Hello Skill
You can order hydroponic nutrient solution from grow stores found on the web.
I don't think fish emulsion will work but I will look into that some more.
Tomato plants are indeterminate which means they grow and produce fruits continually so 20 hours
of light would be good.
Yes you can water continually but cut back if the tomatoes start to split from over watering.

I am VERY new to the hydroponic game, and I am thinking of getting a PVC pipe for a drip system,
I may have to put it on the roof if my Wife has any thing to say about it. My question is, what size
PVC pipe is good for tomatoes
? How big should I cut the holes? and how is the best way to cut
them with, a elect. jig saw? How often should the holes be and how far apart?
Thanks very much for your help
Greg B grb@herald.infi.net Fort Laud. Fl

Hi Greg
You can use 1 1/2" up to 4" pvc pipe for a drip garden.
I like 4" sewer pipe because it's cheep and flexible and easier to drill holes for the bleach bottles.
Use a 1 1/4" hole saw to make the holes at least 18" apart because tomato plants can grow up to 15 feet.

Questions from a newbee:
1. What grow medium would you suggest as alternative to Rockwool and where can you get them?
2. Building the 11 plant hydroponic garden.
a. What kind of pump do you use for the 16" x 23" Rubbermaid storage and where can we get it?
b. What kind of glue do you use to prevent leaks?
c. In my patio I have only two plugs. What kind of extension cord would you suggest in order to
have many pumps running?
d. How much does this system cost for parts? Estimate.
e. How can you make a frame around it so you can hand string to support the tomatoes?
f. What kind of food do you use and how much?
g. What if you want to expand?

Hi Carol
I like grow rocks because they are reusable
You can order grow rocks and other hydro supplies at your local grow store or on the web.
For small gardens a 120 GPH submersible pump size measured in GPH (gallon per hour) is fine but
you can use a larger pump and use a flow valve to slow the water and then open it up as you expand your garden.
You can get Rubbermaid containers at K-mart or Wal-Mart.
You can use 3/4" or 1" PVC to build a stand for your garden.
I would go with the 9 plant garden if you plan to expand in the future.

Hi Ron, I seem to be having problems with keeping my pH down within limits. I bring it down and in
12 hours its back up above 6.7 What do I need to do to get it to hold? Thanks Lon

Hi Ron:
I want to thank you for your hydroponic web site. It has inspired me to try and build one.
More questions:
1. What is ppm and TDS?
2. Where a good place to get a PH reader. They are so expensive.
3. This may sound like a dumb question but how do you get all those Clorox bottles? I think it'll take me several years to get that many bottles. Alternatives?
4. To get those pumps, do you have to go to a hydroponic shop or can you get them at a hardware store?
Another question. In your pipe diagram you're using a 1/2" pipe.
Have you tried using 3/4", 1" and
larger pvc pipes in your design? What kind of pump would you need for a 3/4" pipe and 1" pipe or
Do you have to increase your water storage tank as well?
How do you figure out the flow rate when you increase the width of the pipe?
What kind of food nutrient do you recommend? There are so many brand names and everyone says they're the best. For a newbee like myself its hard to know which brand to buy. I like in the tropics.
Avg temp 85 degrees.
Carol trekker@lava.net

Hi Carol
ppm is (parts per million) and TDS is (total dissolved solids)
You could get by without a TDS pen just by keeping track of how much nutrient solution you add to your tank.
But I would change the water more often maybe every two weeks encase you lose track of the solutions ppm.
I buy bleach by the case to clean my commercial size hydroponic systems and grow rocks so I end up with a lot of bottles. Plus I have all my friends save their bottles for me also.
You can get submersible pumps a HomeDepot and TrueValue hardware stores. Fish stores have them to but they cost more for some reason.
At one time I used 3/4 pvc but you have to file or sand a little off the 2 liter bottle threads in order for it to fit into the 3/4 tees.
Or use a 1 1/8 inch hole saw to drill out the tees and then hot glue the bottles in the 3/4 tees.
Because 1/2 inch pipe fits perfectly inside the 2 liter bottle with no filing or drilling I switched to 1/2 pvc and it's cheaper.
For nutrient solution I use Formula One from
Worm's Way
7850 N. Highway 37
Bloomington, IN 47404
Fax:1-812-876-6478  Phone 800-274-9676
URL http://www.wormsway.com

You can use any solution as long as it says that it is for hydroponics and not for soil but some members do say they have good results with Miracle-gro.

I have a grant for the coming year and my 2nd graders are responsible for setting up the hydroponics
lab for our mock space station.
I have been overwhelmed with the amount of information available. Is there a kit you have which you
would recommend for a small vegetable growing project? I would like something that is kind of a
closed system, although I know we can't duplicate the Nasa CELSS project.
Suggestions for a kit my husband could put together? Suggestions for a good book that would help
me stay a step ahead of my 7 year olds?
Thanks in advance.

Hello Susan
The best book on hydroponics is by Howard M. Rush, HYDROPONIC Home Food Gardens.
It explains how to build a number of hydro gardens.

To the Teacher needing kits.
I have several kits available please email me with your needs and I will send info and prices.

Hi Ron
Remember me I'm the person who needed a 12 volt timer for my hydro unit.
Well after a bit of research I found a circuit description for a long-term linear timer using the 555 chip.
After some experimentation with various resistors and capacitors we have a 12 timer with a cycle
time of 27 min off and 40 sec on. adjustable to 1hr off and 2 min on. By varying 1 or more of 3 parts
the on/off cycle is almost unlimited.
The best part is it cost less than $30.00.
Any one wanting a parts list and circuit description please email me directly and I will be happy to

I would like to know the low and high prices of Hydroponic Tomatoes to super markets in the
Riverside, CA market area.

Hi Ron I Am Currently running a Hydro-Organic system that I want to keep Organic as Possible. My question is of PH. In a issue of Garden Gate Magazine 12/96 They mention to adjust PH before adding any Nutrients to the water. This is probably going to sound bizarre but to raise PH they suggest to add Aspirin. Thats right 2 asprin tablets to a gallon of solution to drop it from 8 to 6. And to raise PH they suggest to use 1 Tablespoon of baking soda into 3 Gallons of solution then wait 10 minutes until rechecking PH. Now before I shelled out my cash for PH up and Down I asked the Sales clerk if  could use Baking soda to raise my PH and vinegar to lower it and he said he wouldn't (Because he wanted the sale I think). Right now I'm using dyno grow ph up and down but I'm going through down quick I need alternatives that are safe for my tomatoes and pepper plants. My system is outdoors and I'm using Earth Juice Products in an active system. If anybody has suggestions, experiences or is into Hydro-organic Gardening please E-mail me...This is all new to me...But I'm determined after spending A Lot of $ Hey thank you for this Web Page I enjoy reading it!!
Rick Sparky701@earthlink.net

Hi Rick
I heard about baking soda but I never heard about the Aspirin. I will check it out to see if it works.
I adjust my ph after I add nutrient solution because I can control my ph just by raising my EC (ppm) with the nutrient solution.

I happened upon your site about 6 weeks ago -- I was browsing the Web instead of working at my desk (shame on me!) I've been interested in hydroponic gardening for a while, but somehow got the misconception that it was difficult, expensive, complicated, etc. After seeing your site I practically RAN to the home improvement store to buy PVC pipe, glue, and a pump. A few short hours later I was gleefully watching my new system fill with water. I built a small, 6 unit hydro system like your 9
unit design. It works perfectly, and now I have a six lush plants in my little indoor garden. I can't believe how well this works. I use a mix of geolite and rockwool in the 16 ounce Solo cups. I think the rockwool holds more water so I have to water less frequently. I found a digital timer at the home improvement center that lets me set up to six events per day for as little as one minute each. This controls my pump, so my system flushes 6x per day for 3 minutes each time. I LOVE my new hobby.
Thank you for giving me the knowledge and inspiration to explore something new and fun!

I have a problem with my tomatoes (3-4') recently developing leaf and stem curl. I am using two different commercial hydroponic formulas from Hydrofarm. Both units are exhibiting the same symptoms.
The foliage seems to be shrinking.  I have been battling whiteflys through the entire life cycle of these plants. They seem to be no worse than when I began but I can't seem to eliminate them.
I just checked my peas and they are beginning to curl also. The leaves are not curling so much as the entire stem seems to to be spiraling back onto itself.
My PH had dropped considerably so I disgarded all solutions and made up new rather than try to adjust.
Any help would be appreciated. I have about 60 plants and sure don't want to lose them now!
Bob Majors- Rockbridge, Ohio rmajors@hockinghills.net

Hello Bob
My tomato plants are curling up and dying now also because of the 95 degree heat.
They still have a lot of tomatoes on the plants but will not grow anymore.
I don't know how hot it gets in Ohio but you might try shade cloth to cool them down and see if that helps.
White flies are a big problem too here in Florida. I use pyritheran to to keep them under control but never completely eliminate them.

What kind of paint do you recommend using on the 2 litter bottles?
Ron Like Vincennes, IN

Hi Ron
I found that vinyl spray paint works best. You can find it at auto stores.


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