Hydroponics - at Home and for Beginners

Step 4 Sterilization

Now, fill your container with water. I am assuming your container is clean and free of debris. Fill to the brim and then ADD 1 TABLESPOON of CHLORINE BLEACH. This is very important as it will kill most intruders you don't want hanging around to cause trouble.

Begin aeration to mix your sterilization solution - put your pots in the container too. After about 20-30 minutes, dump all the water and then allow to air dry completely to get rid of the chlorine.

Once this is done, move on to your initial fill and prepping your medium.

Comments

[xlioilx]

I personally would not add bleach. If you want chlorine in your water the tap water would be more then enough. I strongly suggest not to use tap or chlorine and if you use the tap let it sit out for a few days. The reason why is chlorine will make your roots grow slowly or kill them and the more root the faster the plant growth. I doubt that sterilization with bleach would do much for long periods of time anyways.

[scottinnh]

I second this. If you want to sanitize the container, use Idophor or Star-San. I have both of these in my house because I use them for cleaning out my homebrew and keg system.

Iodophor will stain plastic and leave a faint iodine odor (not very strong) if you dilute it as directed. Star-San is a nice foaming cleaner AND sanitizer (but it will not do both at the same time.. ie, don't think you sanitized anything if your star san solution is full of organic floaties.. dump, rinse and re-apply to sanitize).

Star-san is nice because it's a mild acid, and becomes inert when dried (but if any were left, it would just break down some of the plant food into simpler organic compounds. Star-san -will- begin to etch and pit metals after 15 minutes, so don't soak stuff in it for any longer. SS is actually not that strong when dillute, and I've used it plenty without wearing gloves, but you need to take some care.

[shortw]

You are right, some plastics are known to absorb chemicals and will release it slowly.
If you have chlorine in the tap water you simple can drop your air stone in it and aerated it for 24 hrs, this will get rid of the chlorine. Some tab water contains chloromine and there is no way to get rid of it, since it is a combination of chlorine and ammonia.
Bleach residue could kill your roots and you end up with a smelly mess. Why sterilize and then you pump air into your solution which contain a lot of airborne bacteria anyway.
Remember, 1 drop of bleach in a quart of water will kill any bacteria you may have on your counter top.
So, I would not use bleach at all for this purpose.
I would get a test kit to check your tab water if you use tab water. If your tab water tests for ammonia and chlorine, you have chloromine in it.

[pigpen]

Xliolix is exactly right about all this, if I am really concerned about the sterility of my gear I put enough hydrogen peroxide (regular from the first aid kit style) to cover the airstone and then do basically the same thing you recommend. Let is blow around the container fully set up and then wipe it down with a clean rag.

[pigpen]

I thought I should clarify - hydrogen peroxide is not bad for roots like chlorine, but also will kill bacteria.