Kelsey: your skipper is wrong. Marine sanitation hose lasts 5 to 10 years before permeation becomes a real problem, depending on the brand. The "good stuff" his predecessor bought in 2018 is now at the end of its life. The smell you are describing is, very probably, the hose's contents permeating through the hose wall and into the head compartment air.

The diagnostic test is simple: wet a cotton rag with hot water, wrap it around the hose at several points along the run, leave it 30 seconds, and smell the rag. If the rag smells, the hose is the source. We wrote this up at length in the December 2025 Daybook entry on a Tartan 37 whose owner had the same complaint for three years.

For replacement, on a working-boat budget: Trident 101 series. About $7 per linear foot in 1.5". A 32-foot gillnetter probably has 6 to 10 linear feet of sanitation hose between the head and the tank. Material cost is around $70; labor is mostly in the routing — one to two days for a careful re-pipe with double-clamping at every fitting and verified no-kink at the long-radius bends.

If you cannot get the skipper to authorize the work, do the wet-rag test in his presence. The diagnosis tends to clarify things. — S.A., Tankage & MSDs.

Mr. Cody: removal is not the only option, and your neighbors are partly right. Lake Union is inside the Puget Sound NDZ (the full NDZ designation includes the inland waters and was effective 10 May 2018). Your Lectra-San is, indeed, a Type I MSD — the standard chlorinating macerator that has been on the market since the early 1980s and remains a USCG-certified device.

The relevant requirement, under 33 CFR 159 Subpart A, is that the discharge function be rendered "incapable of being used" while inside the NDZ. The Coast Guard accepts several mechanisms for this; the most common, on Type I units like the Lectra-San, is a padlock on the discharge through-hull's seacock handle, with the key kept off the boat. A wire-tie closure on the discharge plumbing also works. A bolted-down closure plate on the discharge through-hull is the cleanest if you are confident you will never use the unit's discharge again.

Practically: you can keep the Lectra-San installed and operable for the remainder of its eight-year service life. It will run when you flush; it will macerate; it will chlorinate. What you cannot do is open the discharge seacock and dump the treated effluent overboard while inside the NDZ. The Lectra-San in this configuration becomes, in effect, a Type III system: the treated effluent stays inside the unit's small holding capacity, and you pump out at the dock.

The closure documentation should be photographed and kept in the boat's file. If a Coast Guard inspector challenges you, the photograph and the install date are what they will want to see. See the MSD primer in this issue for the full regulatory context. — S.A., Tankage & MSDs.

Tom: the answer depends on what you mean by shoulder season. For the May-through-October active charter season, a two-times-per-year preservation flush (one in April pre-season, one in October post-season) is the standing recommendation for any membrane that runs at least one charter per month. The between-charter polish cycle — 30 minutes of operation after every charter to flush fresh product water across the membrane — is what keeps the biological-fouling clock from resetting between charters.

For the November-through-April off-season, a membrane that will not be run for more than 30 days needs the full October preservation. If you anticipate any of your charter boats going into seasonal storage for less than 30 days at a stretch, no preservation; if more than 30 days, preserve. The propylene-glycol / sodium-metabisulfite solution is good for six months.

For your Sea Recovery Aquamatic from 2014: same schedule. The Aquamatic uses the same Filmtec SW30 membrane family; the preservation chemistry is identical. The only difference is the unit's interface to the preservation solution. Sea Recovery sells a pre-mixed two-quart jug; we keep a case at the shop and sell them at our cost ($38 each) to fleet operators.

The shop's annual preservation clinic at the Northwest Maritime Center on the second Saturday of October is open to fleet operators; we can do all four of your boats in one morning if you bring them. Last year's clinic preserved 23 units in three hours. Register through Tilly at schedule@bhwet.example. — B.H., Watermakers.