I "retired" from spending several hours a day online answering the same questions I'd already answered at least 15 times over 20 years, but I still lurk in 3 sites. I always enjoy reading this one! But old habits are hard to break, so like an old fire horse who smells smoke, I can't resist jumping in occasionally. And I'm glad to help out any folks who email me.

Charlie...when it comes to joker valves...if it fits your toilet use it. Because joker valves should be changed annually anyway (explanation added to the end of this post), so durability isn't really an issue.

Doug...muriatic acid won't harm anything unless it's left in the system too long. Raritan, before they began offering their own seal water mineral "remover," recommended it to clean the electrode pack in the LectraSan for decades. Recommended length of time in the system to get the job done; about 45 minutes.

Thanks for the plug for my book, Bruce...it's available from the sbo.com online store and also from Amazon, plus quite a few boat stores. I need to update it, and I have most of the notes together now, but I'd rather play golf than sit here and work on it! Among those notes is a piece I've called "Joker Valve 101"...since it's anyone's guess when or if you'll be able to read it in a new book, I'll share it with y'all now:

JOKER VALVES 101
Most people think that the only thing the joker valve does is acts as a check valve to stop backflow from returning to the toilet or odor from the tank from escaping through the toilet. But that's not a joker valve's most important function...in fact, the joker valve is THE single most important replaceable part in a manual toilet.

Here’s how the discharge half of the pump works: On the upstroke of the piston, a vacuum is created in the area beneath the piston. This causes the joker valve to close tightly, and the flapper valve beneath the pump to open, allowing some of the contents of the toilet bowl to be drawn into the bottom half of the pump. Then, on the down stroke of the piston, the flapper valve is slammed shut, and the effluent is forced out of the bottom of the pump, through the joker valve, and off down the line. But when the joker valve becomes worn and/or there's a buildup of sea water minerals on it, it can no longer seal tightly on the upstroke of the piston...less vacuum is generated when you pump it. And as it becomes more worn less and less vacuum, till finally the bowl contents simply move up and down a bit, but don't go anywhere. Sometimes the flapper valve needs to be replaced too, which is why toilets should also be rebuilt at least every 5-6 years as PREVENTIVE MAINTENANCE.

You prob'ly won't notice the loss of efficiency at first because it's so gradual...same as we don't see that we've gotten a little older than we were yesterday when we look in the mirror each morning. But I guarantee you that if it's been two years or longer since you replaced the joker valve, you need to pump the toilet at least 50% more times to move the bowl contents to the tank or all the way out the thru-hull....IF they're getting there at all any more.

Marine toilets have moving parts that require maintenance. PREVENTIVE maintenance is called that because it PREVENTS problems that have to be fixed. You get to do PREVENTIVE maintenance on YOUR terms, when it's convenient for YOU...unlike repairs, which NEVER are needed at a convenient time.

And now, since Bruce seems to have solved his problem, I'll tiptoe back out the door.

Fair winds!

Peggie