I think of this as an adjunct to my book "Keeping a Cruising Book for Peanuts," although certainly there is some overlap. I've tested a lot of stuff. Many of these items were mentioned in some prior post--use the search function to find more information.
While you're at it, subscribe to Practical Sailor Magazine. The product descriptions are better, there are comparisons and options, and the test methods are explained. They research stuff I avoid, like electronics. One good find--or bad purchase avoided--and it'll be the smartest $39.94 you'll ever spend.
Oh that smell. The hoses permeate, stink coming through the walls. The stuff in the tank is indescribably, and whenever someone flushes we know. And when you go to pump it out it's slow going. Or rather that is the way it used to be, until I made a long (ugly) study of this for a series of articles and for my own sake. Now all is peaceful and sweet-smell. Well, darn close.
21. Hoses. A holding tank hose should be be odor-proof, easy to bend, easy to clean, and inexpensive. Unfortunately, you can only have two of these, and odor-proof is obligatory, a least in my recommendations. That rules out all "white" hoses and all standard water or exhaust hoses.
My recommendations? I actually have had all of these (and some others) installed on my boat for at least five years, or I would not recommend them. I'm sure they will last 10 years +.
- Trident 101 (black) or 102 (white). Stiff, but rugged as hell. Probably the best value, if you can make it fit. It is NOT as stiff as the dreaded white hose. Get black, because the white is hard to clean.
- Raititan Saniflex. The most flexible hose available, this will go places no other hose will. A good reputation for resisting permeation, and perfect for the DIY.
- Shields Poly X. With a lifetime warranty and the easiest cleaning, this is a best... but there is a steep price. Still, it is a nasty job, so I think it is worth it.
- For vent lines (3/4-inch to 1-inch) you will have to use Shields 140 "white" hose. These upgraded hoses are not available in smaller sizes. Do not use any other hose for vents--clear vinyl permeates within weeks.
Tips: A few simple trick can make fitting hoses simpler:
- Always flush will lots of water before you start. A vinegar flush with some soak time also helps.
- Work in warm conditions. All hoses become stiff in cool weather. If you must work in the winter, warm the hoses and heat the work area to sauna-temperatures.
- Lube with K-Y (no wise cracks). It was invented as a surgical lube, with the requirements that it wash away easily and not damage any rubber type. Lubing with grease can damage the hose and reduce sealing security. Glycerine is also good.
- Never use a sealant on the hose barb. It will leak and you won't be able to fix it. If you need a sealant there is something wrong with the fit or the barb.
- A radiator hose pick is handy when it is time to remove the hoses.
- Add a 90 bend if the hose can't make the turn--it is better than forcing it and making a kink. In fact, there is no reason you can't use PVC pipe for large parts of the run, so long as there is flexibility at both ends.
- Standard American hose barbs don't fit sanitation hose--head vendors sell smooth (not barbed) fittings for sanitation hose. Double clamp (screws on opposing sides) and never use them for a pressure application.
- Soak the hose ends in boiling water if they don't fit. It really helps and it works better than a hair drier. But do be careful not to spill it on your lap.
Left to Right: Jabsco, Groco, and Rairitan. The Groco valve is cheap, but it is stiff and is not recommended. Funny, that they are all the same basic size.
22. Raititan PHII Joker Valve. I bet you have a Jabsco manual head. Most people do. after a year, water starts to seep back into the bowl, even if you flushed enough water and pumped enough dry strokes. Well, the Rairitan PHII joker valve is interchangable with the Jabsco valve and lasts 2-3 times longer. The cost is greater, but measured in $/year it is cheaper, and the labor savings is material.
23. Chemicals. Practical Sailor did a bunch of testing of chemicals, and those based on either Nitrate or enzymes generally worked very well. They work by supplying oxygen in an alternate form (nitrate) so that the bugs do not have to use sulfate and make bad smells. Forespar Refresh was a favorite, along with Odorlos and No-flex. My favorite is Camco TST Ultra Concentrate Singles. What does not work is the nasty traditional blue stuff. At least one brand still contains formaldehyde, a known carcinogen. It also does not work nearly as well.
Camco TST Ultra as a spray keep the bowl fresh and clean.
My favorite trick is to use it as a bowl spray, rather than to dump it in all at once. I dilute it about 4:1 in a small spray bottle, and then spray the bowl liberally with a few pumps after use. In addition to clearing the air, it treats the waste in the hose, something a one-time dose in the tank will never do.
24. Vent Filters. Actually, I would rather see you solve odor problems in more basic ways. Stink (hydrogen sulfide and other mercaptans) result from waste being digested under anaerobic conditions. Just add a little air and the bugs will make carbon dioxide instead. The air does not need to penetrate to the bottom, because the bugs near the top will eat some of the stink burbling up if they have enough oxygen to work with. But then why did they make sulfide (S -) and from what? They made it from sulfate (SO4 2+) because lacking air, they needed a source of oxygen. The sulfate came both from the waste, but more so, from the seawater we often flush with. So if we shorten the vent, increase the size to at least 3/4-inch, and flush with fresh water, that will all help. The above mentioned nitrate (NO3 +) will also provide oxygen. Finally, we try to locate the vent away from air intakes. My problem was that the vent was right under a salon air intake. It would have been easier to move it, I suppose.
Big Orange OEM is refillable and has a built-in vacuum break. The original Big Orange is a monster, suitable for live aboards and multi-head tanks.
If you can't fix the problem and move the line, there is always a vent filter, which I have explained in depth. I recommend one (Big Orange makes some nice ones), but I would rather you made your own.
25. Pumpout Procedures. The biggest goofs are not flushing enough water in a misguided attempt to stretch holding tank capacity (makes the waste too thick and shortens hose life) and flushing anything other than waste and single-ply tissue. Even Kleenex can be fatal (if it can survive the laundry in your pocket it certainly is not going to dissolve in the holding tank). However, the third most common goof is not removing the entire length of the pump out hose from the hook and laying it flat on the dock. Every time the liquid must rise up a loop, that increases the suction lift, and if there are four loops left on the pump stand, that's an extra 12 feet of lift. Adding viscous drag and the lift from the bilge, that's more than the pump can do, and pumping will be slow or unsuccessful. Lay the entire hose on the dock.
Finally, do NOT use vegetable oil to lube the head. It seems like it works, but it causes the waste to clump-up, causing pump-out problems in the future. I did a lot of testing for magazine articles, and adding oil was the only thing that correlated with sludge build-up. Makes sense. This is the reason it is illegal to discharge cooking oil into the sewer, except instead of a legal penalty, you will simply have a tank full of sludge. That's pretty real.