My experience with a marine head is only the last year I've owned the boat and rebuilt the system.
However, I owned a 30' travel trailer for many years. My (now ex) wife and I spent many weekends and vacations in that trailer over the years. It had the same waste system as the boat, the only exception being the boat head has a joker valve and long sanitation line to the tank, where the trailer's toilette sat directly above the black water tank, so when you opened the flapper to flush you could see directly into the tank. And, directly smell the odor with every flush!
I cut my sanitation teeth with that system. I've done everything from maintaining a healthy system to the horrible experience of breaking down the "brown pyramid" with a spray wand. I still have nightmares of that event.
I've also tried many products in the black tank, from green to enzymes to natural....you name it, we gave it a shot. Nothing, and I mean nothing, worked better than good old fashioned Thetford blue with formaldehyde. Yeah, it's not so good for the environment, I know, but when you want to break down waste and control odor, that stuff is potent. Folks can argue with me all they want, but it won't change my mind because I've tried it. Direct experience and some pretty traumatic events.
I've thought about running a line (with a check valve of course) from my fresh water tank to the head inlet to use fresh, treated and chlorinated water to flush....rather than using lake water coming in through the bow seacock....but this has been discouraged (rightly so) by several people because of the slight possibility of contamination....however, I don't drink or cook from the fresh tank. I only use it to wash hands, body, dishes. I keep bottled water on board for consumption and cooking.
However, I owned a 30' travel trailer for many years. My (now ex) wife and I spent many weekends and vacations in that trailer over the years. It had the same waste system as the boat, the only exception being the boat head has a joker valve and long sanitation line to the tank, where the trailer's toilette sat directly above the black water tank, so when you opened the flapper to flush you could see directly into the tank. And, directly smell the odor with every flush!
I cut my sanitation teeth with that system. I've done everything from maintaining a healthy system to the horrible experience of breaking down the "brown pyramid" with a spray wand. I still have nightmares of that event.
I've also tried many products in the black tank, from green to enzymes to natural....you name it, we gave it a shot. Nothing, and I mean nothing, worked better than good old fashioned Thetford blue with formaldehyde. Yeah, it's not so good for the environment, I know, but when you want to break down waste and control odor, that stuff is potent. Folks can argue with me all they want, but it won't change my mind because I've tried it. Direct experience and some pretty traumatic events.
I've thought about running a line (with a check valve of course) from my fresh water tank to the head inlet to use fresh, treated and chlorinated water to flush....rather than using lake water coming in through the bow seacock....but this has been discouraged (rightly so) by several people because of the slight possibility of contamination....however, I don't drink or cook from the fresh tank. I only use it to wash hands, body, dishes. I keep bottled water on board for consumption and cooking.
