Using my brain for once

Over the weekend, I was contacted in reference to a VERY old post I put on a forum where I talked about solutions for water quality issues in fish farms. As I've mentioned a thousand times before, I spent a lot of time and money to become a marine scientist in my yoot, but in the end found it to lack satisfaction to both mind and bank account. I am a simple person but I also like money. Not much opportunity to be those things on the trajectory I was carving out. So, it was a big surprise when a few days ago I got an email from a forum post I made like 10 years ago on the subject. There's this whole backyard industry for moneyed people with time, space and energy who want to grow their own fish and plants on little cottage farms. I haven't kept up with the trend, as I no longer travel in those circles. In a chain of emails, the person who read my post told me that he wishes to expand his 500lb a year backyard tilapia tanks to a commercial level operation. It was fun to talk about, as the guy is in New York State, within easy trucking distance to NYC and had an idea about getting a labeling campaign about his 'clean' fish, tilapia being of questionable provenence when you buy it from a store. It turns out the guy stalked me a bit, which is flattering, as much of the work I did on the subject isn't available online, as I signed away any intellectual property rights to much of my work. So, we talked about design aspects, contingency planning, resources for consulting, applicable law (me being out of date, I still feel pretty confident that the EPA are still soggy and hard to light when it comes to permitting issues) and esoterica. and man, it's good we emailed, as brains, like iron tools, rust when disused. I found that I could still do the caveman math pretty good, but stuff I haven't thought up in years, like mitigating pump head loss to friction (lot of friction is caused by moving water, requiring bigger pumps or optimized systems to cut down pump size requirements) or Biological Oxygen Demand, bigger brain stuff. I can no longer recall the math for making good homes for beneficial bacteria, things like surface-to-volume ratios, etc, and I had to do a lot of pecking and hunting online to find information that I used to have on command. Ah well, time wounds all heels, I guess. It was really fun to break out and do critical (caveman) math on a napkin like in the old days. I regret not being up to date on technology in this area, as it was nice to use my brain for once.