This week's highlights: Root Breakthrough, Dimmer Battles & The EC thingy
Another week down! Since my last update on September 13th, the girls have made some serious moves. Here is the day-by-day log of what’s been happening inside the tent:
The Story So Far:
September 14th – Minor Tweaks & One-Handed Light Gymnastics
Adjusted the pH back down from 5.8 to 5.5. I also wanted to bump the PPFD up to 350 µmol/m²/s. Since the somewhat finicky built-in dimmer on the Lumatek ATS 300W Pro only allows adjustments in 25% steps—and I’m far too stingy to buy additional control gear so I had to lower the light physically. Doing that with only one hand was… an experience, to say the least! The bright side? As the plants grow upwards, the PPFD will naturally increase on its own. I just need to keep an eye on the canopy distance. Once the roots hit the main reservoir, I’m expecting an explosive growth surge anyway.
September 15th – Steady Cruising
Noticed the EC drifted up slightly to 1.3 mS/cm. Left it as is. Just brought the pH back down from 5.7 to 5.5.
September 16th – Quiet Day
Nothing major to report. The pH only rose to 5.6. My threshold for this phase is 5.7 so I don't bother adjusting down to 5.5 until it hits or exceeds that mark. Minimal effort, maximum chill.
September 17th – We Have Touchdown!
pH crept up to 5.8, so I dialed it back to 5.5. More importantly: roots from BOTH plants have officially broken through into the main reservoir! Game on.
September 18th – Smooth Sailing
Just letting the plants do their thing. No intervention needed.
September 19th (yesterday) – Reservoir Change & A Quick Lesson on Canna Schedules
I did a full reservoir change and prepared the mix for Vegetative Phase I strictly according to the Canna Aqua calculator for 30 liters. I input my custom base EC of 0.28 mS/cm and dosed everything down to the exact milliliter using syringes (66 ml Vega A+B, 60 ml Rhizotonic, 75 ml Cannazym). After letting the solution sit for 2.5 hours to settle, I took a reading expecting the target EC of 1.4. Instead, the meter hit a whopping 1.78 mS/cm!
The takeaway here: official feeding charts are guidelines, not absolute truth. Especially when working with remineralized RO water, which reacts quite differently than standard tap water. To bring it back down to a safe 1.4 EC, I had to scoop out 6.5 liters of the hot solution and dilute it back up with fresh, remineralized RO water (EC 0.28). Always double-check your readings before feeding your roots!
September 20th (today) - pH correction from 6.1 back to 5.5 and video editing for this week's report.
Now that the roots are drinking directly from the reservoir and the fresh nutes are locked in at 1.4 EC, let's see how fast they explode next week!
A Note on VPD & Climate Controls:
You might notice I’m not running a high-end, dynamic VPD-controlled tent with automated humidifiers or smart exhaust triggers to chase the absolute textbook 1.0 kPa around the clock. Why? Because this is a Lazy Grow (maybe not for so long, still thinking about mainlining), not a NASA cleanroom operation. Looking at my environment logs, temperatures stay nicely between 22°C and 26°C with RH hovering in the 50–65% range. This puts the VPD naturally right in the sweet spot for veg (~0.9 to 1.1 kPa) without me having to micro-manage humidifiers or drain my wallet on automated climate gear. Sure, dialing in VPD to the exact decimal point might squeeze out an extra 5% of dry weight in the end, but ambient room conditions are doing 95% of the heavy lifting just fine. Good enough for me!