Jump to content

Dwc Slime Slayer: Compost Tea


Nix
 Share

Recommended Posts

Deep Water Culture or DWC for short is one of easiest, highest yielding methods in hydroponics. It is also unique in that roots are suspended in water for their entire lives. That is why the plants grow so large so fast, but it is also a weakness.

 

Among those weaknesses are:

- It uses a large volume of water and because of that, it also uses a large amount of nutrients.

- Plant sites are heavy, usually too heavy to move when full.

- Water must constantly be aerated, requiring powerful air pumps to be run 24/7.

- If using a RDWC (Recirculating Deep Water Culture) then a water pump must also run constantly to keep nutrient levels the same in all plant sites. All of these pumps can raise your electric bill.

- And last but not least, all of that standing water creates a perfect environment for brown slime algae (aka cyanobacteria) to thrive.

 

The slime starts out as a clear snotty film on roots, airstones, pumps, or anything else in the system that is underwater. It quickly turns into a white thick snot that will latch on to your plants roots and from there, suffocate them. In as short a time as one week, roots can go from healthy to a brown rotting mess. Needless to say, this is death to the plants above.

 

I have had the slime appear in bubble cloners as well as my 40 gallon RDWC. In a RDWC, this bacteria (that lives without light) can destroy an entire crop. But fear not, there is a way to kill it and as a bonus, you plants will grow even faster than before.

 

gallery_15206_691_23905.jpg

This is how the slime first makes itself known in a nutrient reservoir. The pump was thick with slime, clogging the flow of water.

 

gallery_15206_691_42580.jpg

Here is a picture of more an advanced cyanobacteria infestation. This was at the end of a grow and as you can see the slime has turned into a thick brown ooze. The only thing that prevented the pump from clogging was a filter bag.

 

HOW TO MAKE COMPOST TEA FOR DWC

 

Firstly, I take no credit for this discovery. I found the recipe while researching this problem. I give credit to a grower named Heisenberg at RIU. If anyone wants the link to a 100 page thread about the tea just message me.

 

Step One is to clean all of the slime out your system. Empty the reservoir. Take out your plants with slime on their roots and put them in a clean bucket. Scrape all slime out of the plant site bucket. Hold up your roots and spray them down with either some diluted H202 or I also like Physan 20 (a fungicide). You can also let your roots soak in a diluted solution of Physan 20 and water for 24 hours if you really want to kill those nasty bacteria.

 

Step Two is to make the compost tea. This tea will be different from the kind you can buy at the hydro store. It will be organic in that it will contain microbial life and fungi but will not contain any plant food. So do not add any kelp or any organic nutes. Also never ever add organic nutes in DWC. If you want to go organic hydro then you should switch to ebb and flow or another method that doesn't involve complete root saturation. Additionally, no matter what the salesperson at the hydro store tells you, never add enzyme products like Hygrozyme to a DWC system. It will make the cyanobacteria reproduce like they're on fertility drugs. Do not add bloom boosters either or the same thing will happen.

 

Get a bucket (could be five gallons, could be fifty, it's up to you), fill it with water, add an airstone, and get some bubbles going. RO water is best, but not necessary. Also don't think that RO water will prevent slime from growing, it won't.

 

Use one handful (per gallon) of General Organics Ancient Forest. This stuff has 30,000+ strains of beneficial bacteria. Put this in a tea bag of some kind. I use paper towel tied up into a teabag. You can also just dump it in a bucket and strain it later. You could also combine some stuff from a local garden store: earthworm castings or peat humus. If you only have earthworm castings, those will do in place of Ancient Forest.

 

Put in some Great White or other product that contains mycorrhizae, beneficial bacteria, and trichoderma. Mycorrhizae is a symbiotic fungi and that keeps crud off your roots. You could certainly just use this alone and see improvement. I use about a half scoop for five gallons of water.

 

Add about one capful of Aquashield (liquid compost). There are other brands of liquid compost available as well. This is the starting point for the microbe reproduction process.

 

Add a few drops of Molasses so the microbes have some food. For five gallons, I add about a teaspoon.

 

gallery_15206_691_6651.jpg

The ingredients.

 

Let this brew for 48 hours then add it to your res and plant sites. You can give about one cupful per gallon. Keep it in the fridge (it lasts 10 days) and keep adding a cup a day until it's gone.

 

There are other products you can use such as GH's Subculture B and M, but I don't have experience with them. The recipe above is fairly cheap considering what you get out of it. The microbes brewed in tea will be more numerous than if you just add the ingredients to your res. Do not add Ancient Forest to your DWC, that part you have to brew as a tea. Even if you are lucky enough to not have the slime you will get improved yields by adding compost tea as the beneficial bacteria and fungi help the roots take in food.

 

gallery_15206_691_204346.jpg

Tea brewing. Sometimes a froth appears, sometimes not. It doesn't matter either way.

 

I make a new batch of tea every two to three weeks. When I begin a new grow or change a res I always add the tea. When starting a new grow, add nutrients and pH down first and then add the compost tea. The reason is the acid in pH down can kill those microbes you just spent two days producing.

 

gallery_15206_691_51666.jpg

If you toss in a sponge or porous rock in the plant site or res, it will give the microbes a place a hang out.

 

gallery_15206_691_70718.jpg

Before long you will have beautiful healthy roots like this!

Edited by Nix
Link to comment
Share on other sites

In your directions you mention using Physan 20. I have serious reservations about using physan 20. Both myself and others I have talked to have used it. I carefully followed the directions and even after flushing the reservoir w/ at least 2x's capacity we found that it killed everything including the plants we latter used the reservoir for.

 

Has anyone else had problems with Physan 20?

Link to comment
Share on other sites

In your directions you mention using Physan 20. I have serious reservations about using physan 20. Both myself and others I have talked to have used it. I carefully followed the directions and even after flushing the reservoir w/ at least 2x's capacity we found that it killed everything including the plants we latter used the reservoir for.

 

Has anyone else had problems with Physan 20?

 

I have used it very sparingly. I only used a very diluted solution to spray the slime off the roots if it's really bad. It is very strong and deadly so you never want to add it to your reservoir or your plant sites. When you spray your roots, make sure it's over a separate bucket or sink. Then spray the roots again with plain water before putting the roots back in the DWC nutrient solution. Sometimes it's not worth it and plant is just lost. If you use compost tea from beginning to end you will never even have to deal with it.

Link to comment
Share on other sites

I have used it very sparingly. I only used a very diluted solution to spray the slime off the roots if it's really bad. It is very strong and deadly so you never want to add it to your reservoir or your plant sites. When you spray your roots, make sure it's over a separate bucket or sink. Then spray the roots again with plain water before putting the roots back in the DWC nutrient solution. Sometimes it's not worth it and plant is just lost. If you use compost tea from beginning to end you will never even have to deal with it.

 

 

Nix,

Thanks for the follow up. With regards to Physan, I had been using clorox to sanitize my reservoir between grows and wanted a replacement since clorox is so nasty. Hydro store guy rec'c Physan instead of clorox. I have since gone back to clorox and am considering using peroxide.

 

Anyway, very interesting post. Slime is a real problem and I will be trying your suggestion soon. As an aside, one can notice the effect of slime on PH. As the slime increases it is constantly dragging the PH down.

Link to comment
Share on other sites

  • 1 year later...

Make sure you dont use Soul Synthetics nutrient line in DWC.  It will kill your plants.

I am thinking you missed the memo about not using organic nutes in DWC. 

 

This is the first line in their product description..."Soul Synthetics Infinity catalyst is a complex blend of powerful organic compounds combined with choice plant nutrition"

Link to comment
Share on other sites

I am thinking you missed the memo about not using organic nutes in DWC. 

 

This is the first line in their product description..."Soul Synthetics Infinity catalyst is a complex blend of powerful organic compounds combined with choice plant nutrition"

no such memo....general organics is the only nutes ive used, for soil, hempy, soilless, and dwc both bubble tote and bubble buckets. nothing but general organics for any of it...

Link to comment
Share on other sites

  • 3 years later...

 

I have used it very sparingly. I only used a very diluted solution to spray the slime off the roots if it's really bad. It is very strong and deadly so you never want to add it to your reservoir or your plant sites. When you spray your roots, make sure it's over a separate bucket or sink. Then spray the roots again with plain water before putting the roots back in the DWC nutrient solution. Sometimes it's not worth it and plant is just lost. If you use compost tea from beginning to end you will never even have to deal with it.

Link to comment
Share on other sites

 

I have used it very sparingly. I only used a very diluted solution to spray the slime off the roots if it's really bad. It is very strong and deadly so you never want to add it to your reservoir or your plant sites. When you spray your roots, make sure it's over a separate bucket or sink. Then spray the roots again with plain water before putting the roots back in the DWC nutrient solution. Sometimes it's not worth it and plant is just lost. If you use compost tea from beginning to end you will never even have to deal with it.

Link to comment
Share on other sites

Nix , in the beginning / original post you mentioned an after slime , I am experiencing this now as I text . My question is how long does it last and do I wash it away , basically what do I do with it . Please help !!!! PLEASE !

 

The idea is to thoroughly get rid of as much slime as you can before doing the tea treatment. Put your plants in temporary buckets and scrub your entire system. Dump the water and take apart pumps, air hoses, air stones, and buckets and bleach everything. Scrub off any slime that sticks to the sides of your buckets or net pots. If your roots are really bad I recommend letting them soak in Physan-20 and water for 24 hours. Spray them down with a spray bottle to physically remove the slime. You need to get rid of as much as you can. The tea is primarily a preventative and it cannot magically clean a heavily invested root zone by itself. Then put it all back together, fill with new water and nutes, and then add your tea. About 1 cup per gallon. 

 

Good luck!

Edited by Nix
Link to comment
Share on other sites

I followed these directions to the letter last fall and the results were disastrous.  I've been using Physan for years to clean lines but had never heard of anyone using it directly on roots.  I made a 1/4 strength solution and soaked 6 of my plants' roots in it for 10 minutes, followed by a thorough flush.  Within 48 hours all of these plants were very dead.  The Physan poisoned them completely.  It would have taken a week or two for the brown slime to slowly kill them off, but in this case they started wilting after a few hours.

 

As for the tea, it didn't stop the slime at all.  I brewed it and added to 3 different DWC buckets, and all had to be emptied within the week after it made a nice organic stew.  I've since gone back to keeping a sterile reservoir by using Dutch Master Zone at each nutrient change along with small weekly additions of bleach (sodium hypochlorite).

Link to comment
Share on other sites

I should have put ratios in the original post. 1/4 Physan to 3/4 water is way too concentrated. I only had to do it once as I have never had a cyanobacteria problem since using the tea, but I think I used around 20ml of Physan to 4 gallons of water. It's very strong. As for the tea not preventing the slime, I assume you did not inoculate early enough. You have to use it right from the beginning of a grow. Just like with good soil, you want a thriving colony of beneficials before you even put a plant in the system. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share



×
×
  • Create New...