Camco TST Drop-Ins Holding Tank Treatment, 15 Pack

The Camco TST Drop-Ins are a simple, no-mess way to keep an RV or boat holding tank working the way it should. Each little pouch goes straight into the tank, dissolves on its own, and gets to work breaking down solid waste and toilet tissue while it controls odor. No measuring cup, no funnel, no powder blowing back at you on a windy dock. You drop one in and you're done.

One bag gives you 15 treatments, and each pouch is dosed to treat a 40-gallon holding tank. That's the sweet spot for most RV black tanks and a lot of marine holding tanks, so a single bag covers a long season of weekend trips or a good stretch of cruising. Because the dose is pre-measured, you get consistent results every time. No guessing whether you added enough, and no wasting product by overdoing it.

Here's the part that matters if you care about where your waste ends up. This formula is formaldehyde-free. Formaldehyde does knock down odor, but it's hard on septic systems and plenty of dump stations and marinas don't want it running through their setup. The Drop-Ins skip it and still keep the tank in check, which makes them a friendlier choice at the pump-out and easier on the bacteria that actually process waste downstream.

Odor control is the whole point of a tank treatment, and this one leans on a built-in deodorant plus an original scent to stop smells from creeping up through the toilet and into the cabin. Anyone who's spent a hot afternoon parked in the sun knows how fast a black tank can announce itself. A treated tank stays civil. The waste-and-tissue breakdown also helps the tank empty more completely at dump time, so you get less buildup clinging to the walls between trips.

A quick word on tank sensors. Most RV and boat tanks read level with probes on the tank wall, and those probes get fooled by tissue and residue that stick after a dump. By helping break that material down, a regular Drop-In routine keeps the walls cleaner, and cleaner walls mean the panel gives you an honest reading instead of showing full when the tank is nearly empty.

One more tip. You don't need to double up on pouches to get the job done. One Drop-In per 40-gallon tank is the dose, and adding more won't make it work any faster. If your tank runs bigger than 40 gallons, step up to a second pouch rather than reaching for something harsher. Sticking to the recommended dose is what keeps the formula easy on your plumbing and welcome at the dump station.

These are built for anyone living with a holding tank. Full-time RVers, weekend campers, liveaboards, and day boaters with a marine head all deal with the same basic problem, and a Drop-In handles it the same way in each. Toss a fresh pouch in after every dump or pump-out, add a couple gallons of water so the treatment has something to work in, and let it ride until the next empty. That's the routine.

Using them is about as easy as it gets. After you empty and rinse the tank, drop in a single pouch, then run enough water down the toilet to give the chemistry a head start. The pouch dissolves on its own, so there's nothing to stir and nothing to clean up. Keep the bag sealed and stored somewhere dry, an RV storage bay or a boat locker works fine, and the treatments stay ready whenever you need one.

If you've been fighting tank odor or dealing with waste that won't break down, this is the low-effort fix. It's the same trusted TST chemistry Camco has been making for years, just packaged in a grab-and-go pouch that takes the mess out of tank maintenance. Keep a bag on board or in the rig and you're set for the season.