So i missed understood. I think they were talking about how the way i do it isn't necessarily recommended. I fill a 5 gallon bucket, make the mix to bring ppm/ph where it should be and dump it in the system.
They recomend doing it with a top off res on a float so it's all very gradual change i believe. I have all the stuff for the top off 13 gallon res for each system but haven't added it to the system yet.
Here's their reply....
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I appreciate your time but I have read the info section several times and just re read it.
It doesn't have any info on the add back that I see.
You mentioned I shouldn't add back nutrients, only plain water, should I ph the add back water to 5.8?
Stability is key in the system. Frequent adjustments are counter productive. You're likely causing yourself issue by micro managing your solution. See copy from our website:
The UC exchanges no less than 5 times the entire system volume per hour. With this being said, getting the pH balanced is a lot less drama then it has been in the past. (Rule of thumb, if the pH is between 5.5-6.5 let it be. Nutrients in this pH range are abundantly available. At times dialing in your solution to the “perfect” pH can be more counterproductive then just letting it ride. If you are experiencing severe pH fluctuations (0.2-0.5+/- a day) you might consider changing to a more pH stable nutrient.
And you say not to adjust the ph with add back, so if this is the case should I let ph get up to 6.5, no higher and then do a full res change? Or is there a different number I should target as the change out point?
If you are using a Top-off Reservoir, you can maintain desired pH and EC/TDS levels by properly adjusting the top-off mix.
pH Example: System started at pH of 6.0 and drifts to 6.5 over a 5 day period, this can easily be offset by making the top off res slightly more acidic (lower) so when top off solution enters system it gradually maintains proper pH levels as the plants access the nutrients.
Gradual pH adjustments made from the top-off reservoir will help avoid any potential nutrient lock outs caused by adjusting the pH with concentrated acid or bases.
EC/TDS Example: System started at 500ppm but has crept to 625ppm as the solution level has decreased. That’s a 25% increase, which can be easily offset by a top off res balanced @ 25% below the initial 500ppmor about 375ppm to compensate.
When operated properly, top off EC/TDS should be balanced the same or slightly stronger as the solution in the system.
Ideally the solution in the system should stay balanced even as the plants use the nutrient and water. This is a good indicator that minerals & water are being used at equal proportions.
Any upward or downward fluctuations in EC/PPM can have an effect on pH. By avoiding excess TDS, the solution is easier to keep stable.
As a rule of thumb if the nutrient EC/TDS rises as the solution is depleted you are likely running your levels too high to begin with. Conversely, if your EC/TDS drops it indicates you’ve started to low.
This EC/TDS stability will translate into improved plant health and greater pH stability.
Observations and slight adjustments are the best way to dial your system, once you have found the “sweet spot” operation of the system becomes quite simple.
Also you say reservoirs can go 14-21 days without changing them but if I'm adding back only water I assume I'll need to change the res more often since ppm will get low? How much can i let the ppm drop with this method before i change the res? For example if I'm supposed to be at 650 ppm, do I let the ppm drop no lower than 550 before a res change? Even if that happens in just a few days?
Use a top-off re as instructed above to avoid add backs and keep your ppm more constant.
Also I was hoping I could get more info on why I might have leaf curl In veg? It seems my ppm and ph are on, water temp is good and roots are bright white.
Likely a reaction to you adding concentrate. We recommend against add backs due to issues such as this.
And what's the recommended res change? Once the ppm goes down a certain amount like if it goes down 100 ppm drain and refill? Or every week or two?
Only need to change out if nutrient pH becomes unstable. Otherwise if the nutrient is being consumed then it is viable.
So just to get this straight never do addbacks? Or don't do them every time? Like maybe every other or every third time?
Top-Off Reservoir: Using a top-off reservoirwill allow youto maintain consistent water levels and follow weekly feeding schedules without dumping valuable nutrient solution. When optimized, a top-off reservoir can be used like a doser for incremental EC/ppm adjustments and pH steering.
Adjusting pH & EC/ppm: Adding concentrated pH adjusters or nutrients directly to the system may result in extreme plant/root shock. Anything added directly to the system should be diluted to at least 20% and added slowly. For best results pH and EC/ppm adjustments should be done through the top-off reservoir.
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Current Culture H2O
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Fresno, CA 93722
559-266-4769
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