well my plants are doing better since i flushed them out. the roots look sort of unhealthy though, they aren't bright white like they are supposed to be. i've read some about adding h2o2 to my res. i have an 8 gallon res which i fill to the 6 gallon mark, dwc system, that circulates water to the netpots constantly (should i not do this?) and this weekend i plan on getting some better nutes and am also wanting to add some h2o2. so my question is how much h2o2 per gallon should i add? i know there are different strengths so which one is the best to use for this purpose (ive read "food strength"). thanks guys
The maxium H2O2 you will want to use is 2 1/2 tsp. per gallon of 3%.Thats what your local store will probably carry.It coms in higher %'s up to 35% but stick with 3%.Its always good to start out on the light side of using it so try 1 tsp. per gallon, along with your nutes,and do a few frequent res changes, at that and you'll see a diff. I guarentee it.I would recomend using it every time you do it res change.Slowly go up to 2 tsp. per gallon, and you'll be pleased.
thanks for the info! i plan on doing a res change on friday after i hit the grow store for some good nutes. i already have 3% h2o2 so that is one thing knocked off the shopping list
I have seen successful gardens use nothing but H2O2 as their source of O2 for the roots. Airstones are actually not required for any DWC, but the added agitations is good I guess. O2 doesn't really like to disolve anywhere but on the surface. Those bubbles rising up do nothing to enrich the water until it agitates the surface, and the bubbles rushing past the roots do very very little as well. Roots need a bit more than .01 second exposure to the free, gasseous O2 to use it for nute uptake. You really want the O2 disolved in the solution for a DWC. H2O2 rules! Plus, it keeps your roots nice and crisp looking. I'm going to try a stoneless DWC myself this time around. The only thing I really worry about is the water temp. Without ambient air being pumped through it, I think regulating the water temp will be more of a concern. And you still need a means of circulating the water and keep it moving. Maybe I'll just use one little stone to keep it churning. We'll see.
I dont think so! I'd like to see the pics of this succesfull garden. I dont see how you are gonna get enough oxygen from just h202. How often do you have to add it? I wonder why every dwc i've ever seen uses an air pump? plus the part of the roots thats above the water level is constantly getting the oxygen that breaks the surface.
Use 35% food grade H202. You will only want to use 2-5 DROPS per gallon in your ressy. Glauc is right in that the bubbles in the solution don't do much until they break the surface of the solution. Once that happens however, the solution is capable of absorbing the O2 because the surface tension has been compromised. H202 is converted to plain old H20 and 02 in 30-60 minutes.
As I mentioned previously, air pumps agitate well and help to regulate the water temp. Many people employ this method the same way as they've seen them set up before, thats probably why you've personally never seen one without a fish pump. Most people do not try to improve and/or innovate a known good idea and design. And that's just fine. The bottom line is, do what you are comfortable with.. as long as it gets the results you are looking for. Thanks Useless. Also, the simple fact that agitated water has a larger surface area than standing water also aids in O2 absorbsion. Temperature is also a factor. Edit: I forgot to address some questions. As far as the rate you'd add it and all that, I don't know for sure just yet. I have experiments to conduct. =) And about the airspace just above the water line.. well, I don't think you need any sort of rushing air.. Unless your plant is a very heavy breather or likes to hyperventilate, I don't see it being any sort of issue. The first 10% of root growth won't breathe for the entire plant and in the big pic, isn't all that important to me in this context.
Seems to me you'd have to have a constant drip feed of H2O2 in the ressy to make that work Glauc. It breaks down too fast to be of any use after 30-60 minutes. Food grade H2O2 (35%) is added to the solution at a rate of 2-5 drops per gallon. The surface area and surface tension are directly related in that a reduction surace tension is a result of a larger surface area. And you are correct temperature plays an important role as well. I gotta say that your proposal could work, however it seems the best (efficient and effective) method is still a powerhead.
