What's new
  • Please note members who been with us for more than 10 years have been upgraded to "Veteran" status and will receive exclusive benefits. If you wish to find out more about this or support IcMag and get same benefits, check this thread here.
  • Important notice: ICMag's T.O.U. has been updated. Please review it here. For your convenience, it is also available in the main forum menu, under 'Quick Links"!

The "Dead Res" Thread

Herborizer

Active member
Veteran
I know a lot of people swear by a dead res. I also know a lot of people are curious about it. The different ways to go about it. The good and the bad, etc. What one might do in DWC might be completely different in Hydroton, Rockwool, or Coco.

I am starting this thread because I often consider running a dead reservoir. This could be a good place for those that have knowledge to share and for others to learn and experiment.

I will start the collective knowledge with information I have found in various threads.

I only know of 4 ways (I bet there are more) to have a dead res.

  • Bleach.
  • Dutchmaster Zone (I believe is cholormine).
  • H2O2 (hydrogen peroxide).
  • UV-C lighting.
Bleach
Krunchbuble, who I trust and respect his knowledge, swears by Bleach. I believe his recommendation is 1 ML per 10 Gallons for maintenance. 2 ML per 10 Gallons to fight an infection (like slime or root rot). Repeat every 3-4 days.

H2O2
I have read a lot of people talk about using H2O2 for running a dead res, but very little about how much to use. I am particularly curious on H2O2 as I believe it could provide other benefits.

UV-C Lighting.
This seems like an awesome solution. Have a pump run your reservoir through one of these lights (usually made for ponds or fish tanks) and sanitize it with no chemical residue whatsoever. Though, after preliminary research it seems that the strength of light, GPH of the pump, and the on/off schedule are very critical to this working in practice. Seems like an expensive and labor intensive route to go down without some best practices laid out to increase success.

Dutchmaster Zone.
I have a bottle of this stuff and have had it for about a year. For some reason I am too timid to use it. Also, it's REALLY expensive.

Anyway, hopefully I have kicked of a fun thread for which we all can learn a lot about and have fun in the process.


P.S. For those that might be tempted to jump into this thread and argue about using Beneficials instead of a dead res, please move on. I agree that beneficials are great and use them. This thread is for dead res and only dead res.

Thanks!
 

teemu shalanie

WeeDGamE StannisBaratheoN
Veteran
when I run hydro i run a dead res so to speak use h2o2 35% @ 1 ml per l every 2 days, but I let it sit 4 hours b4 running it through system.
TS
 
E

Eatatjoes

My opinion on the four options are as follows:

Bleach: My favorite for a dead res because it's cheap it works great and it doesn't have to be added too often. Proven tried and true

H2O2: 35% I've tried it, it works ok. not as good as bleach though and it takes too much and costs too much.

UV-C filter: I've read about them used in commercial hydro greenhouse systems. They work but they react with nutrients in a bad way. (cut and paste) Iron and Manganese ions oxidize and precipitate out of solution causing problems of staining and nutrient deficiency. This process is exacerbated when the water is sanitized with UV light or chemicals.

Zone: Never tried it, way too expensive for my taste. MUCH cheaper options.

I've ran a dead res in a greenhouse DWC system all summer during 115 degree ambient temps with NO rot problems using $1 worth of bleach. BLEACH!!!!!
 
E

Eatatjoes

Here is some more info I found on the web:

There are a number of types of sterilizing techniques. Some are slow sand filtration, heat treatment, ozonisation, UV (ultra violet) treatment and 'ultrafiltration'.

Heat treatment involves heating the solution to over 95 OC (203 OF) for 30 seconds. Heating is done in a counter current heat exchanger where the hot treated nutrient solution is used to heat the incoming untreated water cooling the treated solution back to normal temperatures. Hence operating costs are fairly low. Most temperate zone glass houses already have boilers for heating, the only capital cost is for the heat exchanger. A difficulty is the fouling of the internal surfaces of the exchanger which can be reduced by lowering the pH of the solution.

In ozonisation, the solution is recycled through an ozone producing machine.

Ultra filtration is similar to advanced reverse osmosis. It uses a machine which has a membrane that permits the passing of nutrient molecules while filtering out pathogens. There are technical problems keeping the membranes clean.

UV sterilisation has problems of reduced efficiency due to dirty tubes and shielding in dirty solutions. It knocks iron out of solution and is relatively ineffective against viruses. The dirt problem is reduced by filtration and automatic mechanical cleaning of the tubes.

Slow sand filtration is slow with flow rates in the order of 100 to 300 Litres/hour per square meter of surface area. Their reliability, and simplicity, is a major recommendation in eliminating Phytophthora and Pythium from recirculating nutrient solutions or drainage water. High efficiency was observed against Cylindrocladium, Verticillium dahliae, Thielaviopsis and Xanthomonas bacteria. There is also a report of high efficacy against a virus, pelargonium flower break (Berkelmann et al, 1993).

Pathology work with Fusarium spp has demonstrated a 99.9% reduction rate of microconidia (small resting spores) which were poorly filtered by early designs of sand filters. It is assumed by researchers that this level of efficacy is sufficient to prevent serious problems with distribution of Fusarium through recirculating filtered water. Fusarium microconidia are more resistant to heat and UV treatment than other pathogens and are most likely to be most poorly controlled by any disinfestation method.

It is important to avoid disturbing a skin that forms on the surface of the sand filter soon after it begins operating. This skin consists of organic and inorganic material and a range of biologically active micro-organisms which break down organic matter.

The filter appears to have biological activity in the top 40cm of sand, thus it is recommended that the filter thickness should be a minimum of 50-60 cm. Over time, some cleaning of the filter bed may be necessary and it is recommended that an initial thickness of 80-120 cm is more appropriate, to allow for scraping off a few centimetres during the cleaning process. Beneath the sand filter are three layers of gravel, which prevent sand from getting into the growing system. Slow sand filters can be housed in such containers as concrete or corrugated iron tanks, or large plastic bins. The pH and conductivity of the water are not affected by the process.

Chlorination or bromination can be quite effective in disinfecting water of serious nursery crop pathogens such as Phytophthora and Pythium.

Hydrogen peroxide dosing can also sanitize nutrient solution while increasing the available oxygen at the plant root.
 
I always use h202 at about 1tsp per gallon every 4-5 days in each of my UC12 setups which hold about 65-70 gals each. I ran bleach but it breaks down into salt which isn't a big deal if you change out your water semi often but I only dump the res 3x times a grow. I also didn't like the build up of white crust bleach left as opposed to h202.

Both worked fine for me though to keep away the nasties, especially in summer when my water temps are higher. I tried running bennes and all I had was problems so I went with the dead res and everythings been good.
 

thinkin

Member
FG Hydrogen Peroxide

FG Hydrogen Peroxide

I am running dead res with Food Grade 12.5% Hydrogen Peroixide.
Idea of using bleach scares me. Poison!

Using Food Grade H202 to correct an unfortunate bacterial issue. (I hate you reveg!)

Here is a schedule I found surfing. (probably from icmag somewhere)

I use daily schedule modified for 12.5%.

Outcome:
This dosage keeps bacteria count low. I cant seem to kill them completely. But problem res is "under control" and second (separate) res is unaffected. so I am happy.


 
Last edited:

HUGE

Active member
Veteran
Peroxide is poison aswell. As they say the dose makes the poison. Spill some 75% peroxide on your hand and then tell me it's not poison. I would say drink some but I don't want you to die.


I am running dead res with Food Grade 12.5% Hydrogen Peroixide.
Idea of using bleach scares me. Poison!

Using Food Grade H202 to correct an unfortunate bacterial issue. (I hate you reveg!)

Here is a schedule I found surfing. (probably from icmag somewhere)

I use daily schedule modified for 12.5%.

Outcome:
This dosage keeps bacteria count low. I cant seem to kill them completely. But problem res is "under control" and second (separate) res is unaffected. so I am happy.


 

thinkin

Member
still not a fan of bleach.

still not a fan of bleach.

Peroxide is poison aswell. As they say the dose makes the poison. Spill some 75% peroxide on your hand and then tell me it's not poison. I would say drink some but I don't want you to die.

If you drink too much water, it can kill you.
Does that make water a poison?

Bleach is a poison. Contains Chlorine. Chlorine isnt good for you. AND.. "Disinfectant by-products that have a nitrogen atom incorporated into the structure are far more toxic and genotoxic, and some even carcinogenic, than those DBPs that don't have nitrogen. And there are no nitrogen-containing DBPs that are currently regulated." (from here http://www.aces.uiuc.edu/news/stories/news4724.html)

No food grade bleach available. (food grade is my line in the sand.)

Hydrogen peroixide contains hydrogen and oxygen. simple and safe. Why mess with danger/poison?


Yes, drinking straight h2o2 isnt healthy. Basically oxygen keeps getting produced while inside your body. It will burn your skin. But for the intended purpose with proper dosage, strength of reaction can be controlled.
 

HUGE

Active member
Veteran
Mayby you should use the google machine. There is absolutely food grade bleach. I didn't say bleach was safer than peroxide. Just that peroxide is poison aswell, which it is. Here is a quick read for you

http://www.drmowrycares.com/Library/articles/GoGreen/Hydrogen peroxide.pdf

http://ucfoodsafety.ucdavis.edu/files/26437.pdf

If you drink too much water, it can kill you.
Does that make water a poison?

Bleach is a poison. Contains Chlorine. Chlorine isnt good for you. AND.. "Disinfectant by-products that have a nitrogen atom incorporated into the structure are far more toxic and genotoxic, and some even carcinogenic, than those DBPs that don't have nitrogen. And there are no nitrogen-containing DBPs that are currently regulated." (from here http://www.aces.uiuc.edu/news/stories/news4724.html)

No food grade bleach available. (food grade is my line in the sand.)

Hydrogen peroixide contains hydrogen and oxygen. simple and safe. Why mess with danger/poison?


Yes, drinking straight h2o2 isnt healthy. Basically oxygen keeps getting produced while inside your body. It will burn your skin. But for the intended purpose with proper dosage, strength of reaction can be controlled.
 

compost

Member
If I use regular bleach in my blumat res that has air stones, will I still have salt residue in the res? Wanted to disinfect the res tonight after I give the plants all a good watering with extras. I figure the chlorine will be gone before they start pulling water again. My concern was that there is regular table salt left as the bleach evaporates? Thanks
 

Herborizer

Active member
Veteran
Use h&g dripclean with blumats. No salt buildup.

FYI. I tried bleach and had soso results. I know people swear that there is no problems, but my plants didvfrom it. I used 1ml per 10 gallons. What would happen is slight yellowing and strange dimples on the leaves.

I am now trying dutchmaster zone at 1ml per gallon. I was wrong before, at 1ml per gallon its affordable. I will report back on results. So far no slime at all with it.
 

blackone

Active member
Veteran
I've heard of disinfecting with bleach before but keeping everything dead with a small concentration... Sounds interesting :) It seems like it's not a problem for the plants but I wonder what the poor mold spores, spider mites, gnats and thrips think about chlorine...
 

Lazyman

Overkill is under-rated.
Veteran
I've tried it all too, and also swear by a dead res after 8 years of having 2-5 reservoirs.

DM Zone is Chloramine, basically a more stable version of chlorine that doesn't offgas very quickly like bleach.

Peroxide, particularly in an aerated res is a joke, it lasts for a few hours and is gone, If you're not putting it in right before watering, you're literally throwing money away. Once every 4-5 days is worthless.

I took Krunch's advice and now use bleach, I fill a small bottle with it and use a disposable eyedropper to put 5 ml per day into each of my 55g reservoirs. Quick and tidy, res looks and smells clean, no more blumat clogs, no more algae floating loose in the res either. Dirt cheap and very effective.

As an aside, I also noted that I have about 600 gallons of coco in my rooms, and not one fungus gnat. Might be coincedence, but it might not as well.

Bleach for the win!
 
D

DHF

Bro....you`re sayin no "dripclean" needed fer coco , but rather 5 ml of "bleach" for each 55 gals of feedjuice ?......

Keep`s the Blumat`s clean and hoonin as well ?.......3% or 6% LM...

Just tryin ta save cash on my headies run ......Never liked the idea of buyin supplements that were chlorine/chloramine based (Zone) for growin dope since it was already in tapwater and readily available........

Just need a copy of the rules....Respect...

Peace....DHF.....:ying:.....
 

OjoRojo420

Feeling good is good enough.
Veteran
Bleach = no root rot = no dinner call for Fungus Gnats = healthy roots all till the end of flowering which = much higher harvest.

I also love it!

Try adding it to seedling water for a stronger healthier head start.
 

compost

Member
I am gonna use bleach in my blumat res in flowering. I use KISS at 1/3 strength in the res along with drip clean. I am using hygrozyme but I can just use that in veg or get rid of it all together.

The only thing I haven't figured out is what I am gonna use instead of Liquid kharma. I had been hand watering once a week for run off but I want to stop doing that. If I get something for the res like LK ille be set.
 
H

highvolt

so would it still be ok to use hygrozyme with the bleach or would the bleach render the hygrozyme useless ?
thanks.
 
Top