Day 15
Today I switched the lights from the Seedling program to the Growth program. I measured around 640 PPFD at the canopy level so a bit high for early veg but I will leave it where it is now and keep an eye out for light stress, and raise the lights if I have to.
I also added a second USB fan for increased circulation. USB fans are great when the plants are small and you don't want the stronger winds that the regular clip fan generates. I also started the clip fan but directed it towards the lights to help keep them a bit cooler.
I adjusted the extractor fan from 60 secs Off/30 secs On to 30 secs Off/30 secs On in order to remove more hot air. This will have to be tweaked further and I'll monitor my temps to figure out a suitable setting. It becomes a balance between temp and humidity. I really wish I had a system where I could set a target VPD and then the system would automatically adjust temps and humidity to follow that target. Not practical in my small setup though but maybe one day...
Temps are always an issue in my setup as I have two powerful lights inside one small tent without AC. I have set the light cycle so that the lights are on during the night but off during the day to help to balance the temp a bit. I'm also considering getting some extension cables and put the LED drivers outside the tent to see if that helps to bring down the temps a bit further. Later in the grow I will use CO2 so that will help a bit against higher temps.
Finally, I watered the plants as they were getting a bit dry. The left plant got 1 liter and the right plant 1.5 liters as the sensor reported that that pot was a bit drier. I reckon it has to do with the plant being larger (almost double the size of the other plant!) I should also really get my ass in gear and hook up the Blumat system so I don't need to worry about hand watering.
Day 16
Nothing to report really except some additional growth, both vertical and horizontal.
Day 17
Watering time again. Gave them 6.2 pH water this time and once again more to the right plant as it drinks more. I guess around 1.3 liters for the left plant and 2 liters for the right one. I tried putting in my small USB humidifier into the tent but I soon realized that it can't share the USB power that the fans are running on so will have to get another USB power cable in there. Didn't expect that small humidifier to use that much power. Oh well, that's a job for another day.
Day 18
The girls are thirsty it seems as I had to water again today according to the Blumat sensors (I really, really need to install my Blumat system as soon as possible but should get the last bits that I need in a day or two). I gave them 2.5 liters of water (pH 6.7) and once again a bit more to the right plant.
I also was able to squeeze in my tiny humidifier into the tent even though the tomatoes are still in there. Turns out that all I had to do was to switch the USB power adapter from the old Samsung one that I used to a more powerful iPad charger. Now it works just fine to run the fan and the humidifier on the same power. The reason why I'm using a small USB humidifier instead of a proper one is simply due to the lack of space in my small tent. This (very basic) humidifier is the smallest one I could find yet have a decent size tank so I don't need to fill it up all the time.
Day 19
The cover crop EXPLODED since yesterday so the first thing I had to do today was to cut that back a bit. I also started brewing some compost tea (AACT). I mixed together worm castings, rock dust, biochar, lime, bentonite, neem meal, kelp meal, and molasses and will leave it brewing for 24 hours and then feed it to the plants tomorrow. Would have liked to add alfalfa meal as well but haven't been able to find any. I usually put my seed starter warming mat under and taped to the brewing bucket to increase the tea temperature and microbial activity.
The plants are doing their thing, a little bit taller and a little bit wider. I will probably top the right plant next week but not sure about the left one as it is smaller so might need another week.
Day 20
The compost tea was ready today after 24 hours of brewing. I fed each girl with around 3 liters of tea (pH 6.8) and as I wasn't planning any foliar feeding this time around I kept the tea unfiltered. So that everything that went into making the tea ended up as a top dressing. I guess I don't have to water for a couple of days after this.
Not much change is plant size but the leaves are filling out.
Day 21
Today was completely uneventful so not much to report except that I probably will top the right plant tomorrow as it is up to 5 nodes.