I am beginning to understand why HPA isnt all that popular. If you want to push it to the max, you are constantly walking a tight rope. Small changes make big differences, and its not always obvious how to proceed.
Still, despite all the trials and tribulations, I am having a blast. This is not your fathers boring old grow!!
As of today, nothing has died - yet, so Im still counting this as a success - so far - but it sure is taking a lot of fine adjusting back and forth on timing, nozzle placement, and orientation, etc. I have almost killed the seed twice and almost killed the new clone three times in the last three days. I almost killed the first clone three times as well.
Part of the problem, is I am trying very very hard to stick to drain to waste. At this point, it would be a major problem to convert to a recirculating system. That is forcing me to keep timings short to keep the over all flow rate down.
So far, the drain to waste part is going better than expected. My highest flow rate so far is about 0.9 gallons per day, Thats with a .5 second ON and 40 seconds OFF. Thats only about 6.3 gallons per week, which is just over 1/2 my use when changing a 15 gallon rez once every 10 days. So, I can up the flow rate a lot and still be at or below my normal nute usage. I was worried earlier today when the pump started cycling way early - after 10 hours instead of 18. Turns out, that at the higher pressures - 120 cut ON and 142 cut OFF, the usable volume on the accumulator tank is down from about .7 gallons to .375 gallons.
Ive been slowly increasing the flow rate, then cutting it back, then increasing it again, etc etc, trying to find the sweet spot. Im not there yet, but it feels like it is something that I can achieve - eventually
The clone is looking fairly happy at the moment, having recovered from another wilt/flop. The seedling fell over earlier to day, but I cant tell if thats because some of the perlite fell out of the hole or if it was getting under watered.
More changes, waiting, change, wait, change, wait...... but at least its interesting