How often to full res change DWC?

[JadedMarxist]

Personally. I have a very acute sense of smell if my buckets start to smell, water gets changed.

Like you I had a steep learning curve to get my dwc dialed in.

Had brown alge and start of root root so I did the enzyme route. And h2o2. Cleared that up stopped using carbs and bamn no more ph down needed. As ph was stable at 5.8. Haven't used enzymes since either. I'd say I start to smell the water every 2-3weeks.

It's Wierd I can smell it but no one else seems too. And when I smell it I can smell it every where I my house but no one else can smell it even standing in the room with buckets cracked open

 

[SmokerBwah]

Full res change 1nce per week don’t just keep adding more water that’s a recipe for salt build up

 

[MHOGSMI]

I'd personally ride nutrients for 2 weeks and top off to reach the ppm you're looking for. Changing rez every week will get expensive real quick. Think I've rez changed maybe 4-5 times in my current grow which I started in February.

 

[SmokerBwah]

Rez change once per week. Unless you like salt build up. Your plants like fresh water and fresh food. Top off your buckets. After a week your plants already drank bout 80 percent of all water. Dump remaining 20 percent and start over. Why keep diluting the bottom murky water when you can just dump and refill fresh. If your plants didn’t drink the 80 percent your either doing something wrong or your early in veg where they can’t drink much yet. Growing is expensive. But your yields will make up for it. It’s more expensive spending 3 months growing shwag than it is to dump out A little old stale water and refill fresh

 

[SmokerBwah]

In fact I know pro growers who do complete flush 2ce per week durring the massive growth phase. Sound like too much but the proof is in the pudding y’all

 

[MHOGSMI]

Not sure what your rez looks like, but after 3wks, my rdwc rez and 5 gallon bubblers are crystal clear. And the water smells great.
We all know what a stagnant rez with murky water looks and smells like. I've had buddies roll through dwc grows doing less than 4-5 rez changes and put out tested 22-23% fire.
I'd like to think the more dialed in your system is, the less you need to actually keep swapping the rez. I've seen and read both ways and have seen great results both ways.
Some of the best pieces of advice I've been given in regards to growing marijuana is "read your plants", and "less is more".
If you have a significant imbalance in nutrients, you'll see it in your plants. And to some of us,, you can smell the significant difference in your water. If you have "salt build up". This normally would show/begin to manifest in some kind of nutritional lock out of something else needed by your plant. When your ph and ppms are fluctuating drastically on a daily basis, this can also tell ya the solution is off. If your plant is nothing but healthy and growing great. Stay the course.
My first go round with 5 gallon bubblers, I followed the "every week" rez change and I felt like the more I changed and swapped the water the longer my plants took to grow. Probably just me. But I feel like after a water change, your lifting and disturbing the roots which can shock. Not significantly by any means. But still shocks. I always feel like after a rez change your plants take a day or two to re- acclimate to it's new solution and temp of the solution. Unless you're putting your rootball back into the exact perfect/same temp of the solution you just removed it from which most probably don't. But I feel after a rez change your plants get dialed in and find that sweet spot nutrient wise and temp wise after 2 days. So a day of shock, 1-2days for the sweet spot to be found again. Then great/optimal growing for 3-4days just to start over again? Wasn't adding up to me.

For a beginner. Yeah, I'd recommend changing out your rez more often to greatly reduce the potential problems that can arise from not having a 100% grasp of what's actually going on in your system and not being able to read what your plants are telling you.

By no means am I an expert nor do I have years of experience of dwc growing. But I can easily say extending my water change until I feel it's absolutely necessary has greatly increased the growth/rate of my plants with absolutely zero ill effect.

"Many roads to Rome." Not arguing or saying anybody is wrong. Not saying I'm right. Just that's it's been done many ways which have yielded great results.

At the end, skill and comfort level
Is what's best for you and what you feel comfortable doing.
"Taking the advice of many great opinions to formulate a solution that works best for you, will give you the outcome you're looking for."
Sorry about the book. Adderall,doughnuts and coffee have spawned this.

Cheers yo!

 

[Nate_in_AK]

Adderall,doughnuts and coffee have spawned this.

Well I hope you brought enough to share with everyone!

 

[threatco]

I've done a few grows in 5 gal DWC buckets. The rule of thumb that worked for me is to do a full res change once you have added 100% of the normal capacity to it.

In your case, normally full is 3.5 gal. So after you have had to top it up with 3.5 gals worth of water/nutes is when you want to do a full res change.

My understanding is this is to get rid of "degraded" nutes that have turned to salts and will never be used by the plant any more but contribute to ppm/ec. You can see these salts as a white residue on the sides of black 5 gal buckets. So that gives you a bit of a visual as to when they are building up.

 

[Mathimus]

A mature plant with an established root system can take up 3 gallons in 4 or 5 days in a non recirculating 5 gallon bubble bucket. Sometimes less. I use 10" net pots in non recirculating bubble buckets for veg only. Just because the roots, when established, are harder to work with and can easily take up more space than your 3 gallons in 5 gallon buckets. I might get a PH and ppm reading once between feedings. But that's only because of repetition and I journaled my dosing and watched how they responded over time.

I will not add anymore nutrient amended water until an average of 5 days later - because the plants take up water and nutrients at an equal ratio. At this point, the water level is less than a gallon in the buckets. I keep a spare 5 gallon bucket to put the plant into when I'm making a new nutrient water batch. Followed by rinsing out the nute bucket then spraying the inside of bucket with a 50/50 water alcohol solution, wiping the inside out, then rinsing it out again. Next I'll do my water, nute and ph down mix so it can bubble mix/stabilize while I address the plant.

After, I use the garden sprayer on rain setting to flush out the top of the plant in the spare bucket. Doing so pretty liberally insures that whatever grow stone media I'm using is rinsed of any salts or contaminates that have leached from the bubble action in the system. Next, I'll usually cut about a quarter to a third of the bottom of my roots off. Then I'll sit the plant back in its fresh water solution. This is repeated every 5 days. The same ratios are always given. Nothing ever changes. No deficiencies ever.

It may seem like a lot of work but it will take all the guesswork out of feeding, eliminates deficiencies, salt buildup, the need for hydroguard, peroxide or any other amendments that can kill beneficial bacteria in your rhizosphere.

So relative to the effort of daily monitoring and adding or assessing feeding needs/deficiencies of the plant, a complete flush and fresh nutrient change reduces those efforts to a fraction once you develop a feeding recipe relative to the type of growth you want to achieve.

 

[threatco]

A mature plant with an established root system can take up 3 gallons in 4 or 5 days in a non recirculating 5 gallon bubble bucket. Sometimes less. I use 10" net pots in non recirculating bubble buckets for veg only. Just because the roots, when established, are harder to work with and can easily take up more space than your 3 gallons in 5 gallon buckets. I might get a PH and ppm reading once between feedings. But that's only because of repetition and I journaled my dosing and watched how they responded over time.

I will not add anymore nutrient amended water until an average of 5 days later - because the plants take up water and nutrients at an equal ratio. At this point, the water level is less than a gallon in the buckets. I keep a spare 5 gallon bucket to put the plant into when I'm making a new nutrient water batch. Followed by rinsing out the nute bucket then spraying the inside of bucket with a 50/50 water alcohol solution, wiping the inside out, then rinsing it out again. Next I'll do my water, nute and ph down mix so it can bubble mix/stabilize while I address the plant.

After, I use the garden sprayer on rain setting to flush out the top of the plant in the spare bucket. Doing so pretty liberally insures that whatever grow stone media I'm using is rinsed of any salts or contaminates that have leached from the bubble action in the system. Next, I'll usually cut about a quarter to a third of the bottom of my roots off. Then I'll sit the plant back in its fresh water solution. This is repeated every 5 days. The same ratios are always given. Nothing ever changes. No deficiencies ever.

It may seem like a lot of work but it will take all the guesswork out of feeding, eliminates deficiencies, salt buildup, the need for hydroguard, peroxide or any other amendments that can kill beneficial bacteria in your rhizosphere.

So relative to the effort of daily monitoring and adding or assessing feeding needs/deficiencies of the plant, a complete flush and fresh nutrient change reduces those efforts to a fraction once you develop a feeding recipe relative to the type of growth you want to achieve.

Am I reading this right? Do you cut 1/4 to 1/3 of the root mass every 5 days? What are the benefits?

 

[Nate_in_AK]

Next, I'll usually cut about a quarter to a third of the bottom of my roots off. Then I'll sit the plant back in its fresh water solution. This is repeated every 5 days.

I'm a newblet at this and never heard of pruning the roots in a DWC grow. Is this something you worked out on your own? Do you have any other reference on this approach? Sounds..... interesting......?

 

[Mathimus]

I'm a newblet at this and never heard of pruning the roots in a DWC grow. Is this something you worked out on your own? Do you have any other reference on this approach? Sounds..... interesting......?

For my application, I run a perpetual veg in bubble buckets until flower. So they can stay in veg anywhere from 4 weeks to 3 months while waiting to go to the larger sites for flower. I should have specified this. I'm talking once the plant reaches what would be considered a mature state for a 5 gallon bucket.

The only reason I trim the roots every 5 to 7 days is for no reason other than allowing the plant to sustain itself longer in a 5 gallon bucket - after the plant reaches its mature state. It's the same synopsis as a plant, in coco or soil, getting root bound in a one gallon pot and needing to be transplanted to a 3 or 5 gallon pot. Except in DWC, you can trim the roots back, which allows it to sustain itself longer in that size bucket/plant site.

I don't do this the whole grow, as it would obviously be harder to do with big monstrous plants in flower under a net.

 

[Aqua Man]

I know this is an old thread but since it was replied to I will throw my 2 cents in.

In a live system I only change 50% of the water max. You can do less and sometimes I do I won't get into how I do because it depends on how lazy I am. But here is what I consider good practice and is a one size fits all solution to water changes. You all gonna laugh it's so simple.

So weekly water changes. how much well that depends on your add backs. Take the total volume of your system. Then add up all the water/nutrient solution you have added back to the system over the week. For ease let's say the system has 40gal of water (actual water) you add back 10gal over the week thats 1/4 of the volume of the system so you do a 25% water change. If it's 20gal then change 50%.

There are 2 ways to do this. Either change the 50% of the water once you have added back 50% of the WATER volume.... Or...

Do weekly water changes based on the % of water added back.

This will keep nutrient ratios in balance enough that you should never see a nutrient ratio imbalance throughout your grow.

That's it... Is that simple and can be applied to any system no matter the size.

 

[Nate_in_AK]

So weekly water changes. how much well that depends on your add backs. Take the total volume of your system. Then add up all the water/nutrient solution you have added back to the system over the week. For ease let's say the system has 40gal of water (actual water) you add back 10gal over the week thats 1/4 of the volume of the system so you do a 25% water change. If it's 20gal then change 50%.

There are 2 ways to do this. Either change the 50% of the water once you have added back 50% of the WATER volume.... Or...

Do weekly water changes based on the % of water added back.

Match check: 5 gal bucket, 3.5 gal water. Over the week I add 2 gal of nutrient mix. Are you saying this leaves 1.5 gal (3.5 - 2) of water that should be 50% changed??

What if I add 3.5 gal of nutrient in a week?

Thanks Aqua Man

 

[AnselAdams]

I know this is an old thread but since it was replied to I will throw my 2 cents in.

In a live system I only change 50% of the water max. You can do less and sometimes I do I won't get into how I do because it depends on how lazy I am. But here is what I consider good practice and is a one size fits all solution to water changes. You all gonna laugh it's so simple.

So weekly water changes. how much well that depends on your add backs. Take the total volume of your system. Then add up all the water/nutrient solution you have added back to the system over the week. For ease let's say the system has 40gal of water (actual water) you add back 10gal over the week thats 1/4 of the volume of the system so you do a 25% water change. If it's 20gal then change 50%.

There are 2 ways to do this. Either change the 50% of the water once you have added back 50% of the WATER volume.... Or...

Do weekly water changes based on the % of water added back.

This will keep nutrient ratios in balance enough that you should never see a nutrient ratio imbalance throughout your grow.

That's it... Is that simple and can be applied to any system no matter the size.

Don't forget to allow for the volume occupied by the roots. This will obviously change as your plants grow. It is a lot easier to deal with if you are recirculating vs not! I found myself adding too many nutes over time because i was not taking root volume into consideration. I actually lost half the crop before i figured it out. Actually it was someone on The Farm that happened to ask just the right question, in just the right way; to cause the ole light bulb to light up!

One of the reasons i have a 40 gallon rez for two plants.

 

[Aqua Man]

Match check: 5 gal bucket, 3.5 gal water. Over the week I add 2 gal of nutrient mix. Are you saying this leaves 1.5 gal (3.5 - 2) of water that should be 50% changed??

What if I add 3.5 gal of nutrient in a week?

Thanks Aqua Man

I would say you need to do water changes more than once a week but could get away with once a week for now prob. 3.5g/2=1.75gal so every time you add back 1.75g of water you change 50%

 

[Aqua Man]

Don't forget to allow for the volume occupied by the roots. This will obviously change as your plants grow. It is a lot easier to deal with if you are recirculating vs not! I found myself adding too many nutes over time because i was not taking root volume into consideration. I actually lost half the crop before i figured it out. Actually it was someone on The Farm that happened to ask just the right question, in just the right way; to cause the ole light bulb to light up!

One of the reasons i have a 40 gallon rez for two plants.

Yeah you definitely need to for nutes. But for water changes it will be close enough although doing so would take it a step further. This is a KISS method so don't wanna complicate it to much

 

[AnselAdams]

Yeah you definitely need to for nutes. But for water changes it will be close enough although doing so would take it a step further. This is a KISS method so don't wanna complicate it to much

My apologies, smoke got in my brain and i fudged the topic KISS is always better!!

I will shut up now and go do another dab!

 

[Aqua Man]

My apologies, smoke got in my brain and i fudged the topic KISS is always better!!

I will shut up now and go do another dab!

Hahaha no bro your absolutely right it is better.

 

[Burned Haze]

Wonderful enzyme concentration for gardening , but for “clogging” sensitive growing like a lot of hydro growing, may not be a good option. For me ( coco) works awesome and ultra cheap!
https://www.amazon.com/dp/B000OVCI2S/ref=cm_sw_r_cp_tai_lllTEb0FPH1FE