Here is the best info I can find on Root Rot, Temps and Prevention of Root Rot:
Ain't no doubt, the temperature is the hardest factor to take control of. When confined to a small space,or even a small room, ballasts and lights can push temperatures sky-high in no time flat. This is especially true during hot summer months when outside temperature reaches its highest. Nighttime (lights out period) temperature can be just as difficult to regulate during cold winter month.
Most gardeners are aware that temperature in the grow room plays a major role and can greatly affect the growth of plants and the quality of the finished crop. Most gardeners do not know how controlling the temperature of their garden in very specific ways they can achieve a superior crop. Drift too far from these ideal temperatures and watch your plants and crop suffer.
Before getting started it is highly recommended that every indoor garden has a max/min thermometer. ($4.95 at Wlamert) This product allows the gardener to see exactly the fluctuations in temperature within their room or grow space. Without this useful tool there is no accurate way of knowing the different temperatures between daytime (lights on) and nighttime (lights off). The difference between the two temperatures is very important to plant growth. Anymore than a 10F-15F difference between daytime and nighttime temperatures and you risk shocking and stressing the plants. In general the optimal daytime temperature for plant growth is between 70F -75F. Drift too far above this range or too far below and growth can be severely affected. Daytime temperatures exceeding 90F or under 62F and plant growth will be stunted. If the temperature drifts higher than 95F the plant’s enzyme production will drop off and the plant will begin shutting down. At temperatures that high photosynthesis shuts down due to the stomata in the leaves closing down to conserve water. At normal temperatures the stomata will be open, taking in CO2 and sweating water to keep the plant cool and allowing for transpiration.
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It is recommended that the nighttime temperature drop no more than 15f from that of the daytime temperature. There is another relationship between temperature and the absorbsion of gases by plants that many hobbyist growers are aware of. That is the relationship between the temperature of the water in your reservoir and the amount of oxygen the water can hold. The best range that your reservoir can be between is 60F-75F. Ideally the reservoir temperature should be at 65F because this level contains the most oxygen. Also this temperature will help control transpiration (the act of drawing up nutrients by evaporating water through out the leaves), and humidity levels. Buying a simple floating thermometer will allow you to know where you fit in this range.
Another great reason for regulating the temperature in your grow room s that biological processes can be speed up exponentially by every degree. This is true for your plants as well as the potential pests that may invade your grow room. Pests such as spider mites can reproduce up to 10 times faster with every degree the temperature rises. These pests can destroy a garden in no time flat, you really do not want to make it any easier for them. With a daytime temperature at a steady 72F and nighttime temperature of 65F it is much easier to control and destroy spider mite, thrip, and many other pest populations.
The same principal can be applied to the prevention and control of fungi, molds, mildews, and bacteria, which can spread more rapidly when temperatures in the grow room or reservoir exceed 90F. Also, the warmer the air, the more water it can retain which means humidity levels can easily go beyond the recommended 40-50%. This high humidity coupled with lower nighttime temperatures can cause condensation to form on leaves. This will invite molds, mildews, fungi, and bacteria to take over you grow space. With high temperatures the likely-hood of losing control of the problem, such as powdery mildew, is very high. Once control is lost your plants may be the next to go.
Temperature is also very important when it comes to starting seeds and getting cuttings to root. Placing seedling trays on a heating mat will reduce germination time dramatically. Speeding up germination time usually leads to stronger and healthier plants. Also, less time spent between crop cycles makes a garden efficient. More harvests provided in less time can equal big bucks in the pockets of professional growers.
The ideal temperature to achieve these results is 80F. Any higher and you risk burning the roots. Also, many seeds simply will not germinate at temperatures over 90F. The seeds will become dormant and never sprout.
The same principal used for seeds is used on cuttings to coax roots out quicker. The sooner cuttings can establish roots the better. If roots can be forced quickly they will grow strong and stay strong. A bottom temperature of 80F-85F, roughly 10F warmer than the air, will speed up rooting time and help to jump start those roots once they do begin. Let the temperature get too high or too low and roots growth will be hindered or they will never grow at all. Using the proper technique and the proper temperature for bottom heat not only can rooting time be speed up from 2 weeks to as little as 3 days, but the survival rate of your cuttings will drastically improve.
On the topic of roots, there is an ideal temperature for the root zone after the plants’ roots have been established. Roots are working 24 hours a day and constant attention is required concerning temperature in and around the root zone. The ideal temp for this root zone is generally 75F. At this temperature the ion exchange between the roots and the environment around them is at its absolute best. This means that the plant’s root system can take up more macro nutrients, more micro nutrients, and more oxygen at this temperature than at any other level. This makes a plant more efficient and a plant working efficiently will provide a superior yield.
Root Rot?
Thick, fat, white furry roots are what you most want to see - they are absolutely indicative of healthy root growth. Be aware however that the color of a nutrient solution will stain the roots, turning them yellow or brown. This is also true of many nutrient additives. Older, more mature plants will have a darker cream-colored root system, and some plants just tend to have a natural cream colored color pigment.
Root Zone Temperature
The temperature of the root zone and the temperature of the nutrient water solution can have a major effect on the healthy growth and appearance of the root system. In general the temperature should be between 68 and 72 degrees farenheit. Anywhee between 64 and 80 will be OK. Colder or warmer conditions can cause poor and stunted root growth, as the roots don't want to grow into the unhospitable nutrient solution. Major root death can occur in even brief periods of cold or heat stress. Poor temperature conditions leave the door open to root disease.
Some would argue that one of the strengths of hydroponics is its sterile environment, and the notion of exposing growing systems to bacterial and fungal organisms would be self-defeating, if not sacrilegious. These growers rely on sterile growing environments, strong disinfectants and a product like
SM-90. Another option is
Hydrogen Peroxide. Each of these offer their own protection and benefits.
But NEITHER SM-90 or Hydrogen Peroxide works well with organic nutes or organic additives in the reservoir.
You can not try to kill the organic algae or pythium and add organic materials back. That just won't work!
They do not work well together and SM-90 has also been known to react poorly with Superthrive.
In a sterile growing environment, your goal is to have a super clean reservoir. This is harder than it sounds. Folks who have been growing in the same area with the same equipment for years might find that they are suddenly having root problems when they never had them before. Or a new grower might begin having problems right from the beginning because of his water or temps.
Keeping your reservoir totally sterile can work very well, but once you get a population of icky badness it will keep coming back again and again. Some pathogens such as pythium are almost impossible to get rid of completelely. No matter how many times you sterilize everything with a bleach solution, the problem returns. It can get very frustrating and expensive to constanly be battling. More and more innovative growers are moving toward a more wholistic approach of using good microbes in the reservoir with organic nutes or staying with strickly chemical nutes..
One option is to use no organic additives at all and to rely strictly on chemical nutrients based on fertilizer salts. We think a better choice is to continue using organic material, but also using an enzymatic addtive like
Hygrozyme that will break down the unwanted organic matter in the reservoir . If you would like to use additives such as bat guano, compost or fish-based products, you might consider run to waste instead of a recirculating system.
Ed Rosenthal says about peroxide:
I found this article very interesting. It was written by Ed Rosenthal, and Major Tom first psoted a link to it. I se a lot of mis-information about peroxide, so I thought I'd start a peroxide thread, to give Hydro growers an opprotunity to share experiences with peroxide.
Here is the article:
by Ed Rosenthal.
How much hydrogen peroxide should be used?
When and how much hydrogen peroxide should I use in my hydroponic solution?
Hydrogen peroxide is a powerful oxidizer that can be used to destroy fungi, molds, bacteria and other infectious agents as well as some pollutants. Adding it to your water helps plants by destroying infectious agents and by adding oxygen to the roots' environment.
Hydrogen peroxide is an essential ingredient in maintaining a clean growing room. It replaces chlorine bleach, which is antiseptic but harmful to breathe. When added to reservoirs, hydrogen peroxide slows the growth of algae and other water organisms so that trays and utensils need to be cleaned less frequently. Soil and water borne diseases such as pythium and other stem and root rots occur at much lower rates in hydrogen peroxide-enriched water. Hydrogen peroxide works because of the oxidative reaction, so micro-organisms are unlikely to develop a tolerance.
There are many ways to add hydrogen peroxide to the water. A measured amount every three days is the crudest method, but still effectively enriches the water. A smaller measured amount daily would even out the peaks and valleys of oxygen in the water. Another method is to use a drip similar to an IV bag, which continuously adds a regulated amount. The most sophisticated method is a probe which measures the oxygen content of the water as an indirect means of measuring the hydrogen peroxide, and adds an appropriate amount as needed.
When used properly, hydrogen peroxide can keep infections in the garden to a minimum and stimulate root growth by increasing the oxygen content of the water. Hydrogen peroxide degrades into free oxygen and water over a three-day period. Some of the oxygen dissolves in the reservoir water and is used by the roots.
Different concentrations of hydrogen peroxide solution are available. It is sold diluted to 3% in drug stores. Some indoor garden shops sell 10% grade and 35% grade is sold in a few health food stores and over the Internet. The 3% hydrogen peroxide solution can be used topically to sterilize cuts and infections. Hydrogen peroxide solution at 10% burns skin. 35% hydrogen peroxide solution acts much like a concentrated acid and is handled as a hazardous, corrosive liquid.
The 10% hydrogen peroxide solution is sometimes used at rates as low as one ounce per 10 gallons water; however, enrichment using an ounce per gallon is more effective for disease control. When 35% hydrogen peroxide solution is used, it can be added at the rate of three ounces per 10 gallons of water. If a 3% solution is used, use three ounces per gallon of water.
ZeroTol is a peroxide-based commercial sterilizing agent used in the greenhouse industry. Its active ingredient, HO2, also breaks down into oxygen and water, but it is even more active than 35% hydrogen peroxide. It is used at the rate of one part per 300, or three ounces per 10 gallons, for excellent prevention of diseases and infections. ZeroTol is available from Bio-Safe Systems in Connecticut (1-888-273-3088; www.biosafesystems.com) and through some other gardening supply stores.
He seems to promote it more as a preventative, or aid, instead of a cure.
Anf as I researched the subject I learned that peroxide is better as a prevetative, than a cure. Like it really slows down algae growth, but it is not 100% effective at removing or killing it all.
I would also add it is NOT to be mixed with organic nutes, that is destructive and like pissing in the wind.
