If one salad = one head of lettuce and each head take 60 days to mature than 60 plants are needed. If you want other stuff on your salad than you’ll need more.

First off: get a pH meter asap, even if it’s a cheapo one. Doing hydroponics blind will lead to failure… unless your really lucky. I don’t see why you couldn’t pick immature tobacco. Your over all harvest will suffer, so I would suggest being as patient as you can be. Drying tobacco is a rather [...]

First off, go for the cheapens meter you can fined. They work well enough for your applications, and often last just as long as the expensive ones. Tobacco is in the night shade family so will have similar requirements to tomato, egg plant, and others… But it’s a big plant. It will need lots of [...]

There is a guy who has made a lot of youtube vids on hydroponics. He has been trying to do the PV thing. He spent a huge amount of money and it still wasn’t working fully last fall. If your doing it in a building that has electricity you should just plug it in. If [...]

@hardwarejunkie Oh good. You can grow under halogen or incandescent, but there are much better options. i remember a book I read many years ago, in some university library, the book was published a long time ago. It was clear that florescents hadn’t been around for all that long and mercury vapor (MV) was a brand [...]

@hardwarejunkie Halogen?!?! As HWJ said; LED’s are really not a great option yet. Even if you make a DIY one, the cost will be very high for a big enough set up to grow one mature plant. The basic WF design is a simple way of using light from a window. If your growing from a [...]

With hydroponics you are continuously feeding them, until the plants have eaten all the stuff out of your water. The timing all depends on the size of your nute tank, and the size of your plants. If you had 150gal tank you’d only have to change it once a year, if that. The best way [...]

Lettuce like a lot of moisture, so it’s almost impossible that you over watered them. It’s likely a infection. Did you smell the roots? I would suggest sanitizing everything. Run 5% bleach solution through the system for a few hours. Drain and let dry for 12 hours and rinse with boiled water, then drain and [...]

I’m not that familiar with the exact set up you have, but you should be mixing your water, nutrients, & PH adjuster outside of the system. Every day or two you should check the PH of the water in the system, and make sure it’s still in range for your plants. And every week or [...]

I see you found something a little classier than PBR

Try adding some hydrogen peroxide to your nutes. Up to 30ml per gal has been show to be beneficial to plants, and it may just kill those little root suckers (or whatever they are). Neems oil is good for many pests, but as far as I know; it really works for pests that attack the [...]

I would recommend avoiding any “horticultural” floro or CFL simply because of the cost. They may have a slightly better spectrum, but it’s only about 5% better at 300% the price. LED’s have a much better spectrum, but the price per watt is 10 to 30 times more that CFL’s… maybe in a few years… [...]

How difficult would it be to have the system respond to additional sensors to change the frequency? I was thinking of temp (h2o & air), humidity, and light. It would take a lot of experimenting to come up with a program that was ideal, but It wouldn’t be a very difficult experiment if you had [...]

that is algae. This can be prevented by blocking light from your nutes (rez. tubes, and silencer). I’ve grown rosemary in soil a few times. It’s strange, as it looks fine for a week or two after it’s dead. Brown spots are hard to diagnose. I’m not that familiar with unhappy lettuce, but it could [...]

Sorry to hear about this. Over lighting is not your problem, but your lights may be. I think heat is likely the problem. Heat can cause many problems like wilt, and root rot. If root rot is happening, the roots will smell like feet. The transplant to the system often shocks plants a bit, which [...]

@izzy, Lead in bleach? where are you getting this? They recommend it for sterilizing baby toys, don’t think it has lead in it, well maybe if you find some from the 1940′s, or buy the generic wallmart brand… Anyway an acid shock could work, I would bother buying vinegar though. As I have a hydroponic set [...]

@angelz , The limiting factor is not likely the nutes. If it were, you would see discoloring of the leaves. Light is the major difference between out doors to in. Unless you live in greenhouse, your plants are getting at best 60% of the light they would get outside. If you want to speed things up; [...]

A lot depends on your plants. Some plants will grow much better if they get more oxygen to their roots, so letting them dry out a little between waterings causes faster growth. Other plants, like lettuce likes it to stay more moist. Also the size of the plant is important. A small seedling will dry [...]

Algae needs light, nutes, water, and air to grow, just like any plant. The only thing you can really starve it from is light. Using black tubing and covering your nute tank is the best approach. Cleaning out equipment that has algae in it already is also a good step. To do a good job [...]

I think it’s possible to make a bonsai tomato plant that will fruit. Trim it back a little on the leaves and on the roots. Keep doing this once a week until it starts to flower, and then just let it do what it will. Keep in mined that it will likely get twice the [...]