I bought a Hunter 29.5 that had been in storage for some time. There are solids in the tank, and repeated pump outs after filling with hose water as not cleared the tank. Is there a way chemically to loosen the solids, and get them out?
Waste Water Tank Solids
- Thread starter H Travis
- Start date
How long do you leave the water in before you pump out? Might need to let it sit in there for a while to 'rehydrate'. Maybe a strong stool softener?
When you are at the boat, you- or maybe your dock mates- need to get the boat rocking to agitate the tank. Usually, some liquid soap, water, and a bouncy sail for a few hours are suggested as a way to CLEAN the tank... but solids are a different thing. Good yuck with this one
If the sludge is still just "mud," repeated applications of a few gallons of water put into the tank using plenty of water pressure via the deck pumpout fitting--'cuz that sends the water into the tank at the bottom to stir up the sludge and hold it in suspension so it can be pumped out--should clean it out. Add a few gallons of water--pump out...repeat, repeat...till you're finally pumping out clean water. But if the sludge has dried and turned to "concrete" on the bottom of the tank, I don't know of anything except MAYBE NoFlex (available from the online store here) that will soften it up again so it can be pumped out that won't also damage the system. In that case, you may be better off just replacing the tank. If the tank is aluminum, it definitely should be replaced anyway. If the hoses stink or are anywhere near 10 years old, they should be replaced ...and depending on the make/model/age of the toilet, it may not be worth putting any money into either, even IF any parts are even still available for it.
Just what you wanted to hear, right?
Just what you wanted to hear, right?
Yes if you can get the solids exposed to the chemicals.
But...
You might use water pressure to "blast most free" first.
https://www.amazon.com/gp/product/B0006IX7YC/ref=od_aui_detailpages02?ie=UTF8&th=1
Jim...
Here's some tips on stool softening. There may be something you can use, like epsom salts. Good luck.
Advise your crew on the benefits of eating more fiber
http://www.healthline.com/health/digestive-health/natural-stool-softeners#1
Advise your crew on the benefits of eating more fiber
http://www.healthline.com/health/digestive-health/natural-stool-softeners#1
That device is designed for use in RV tanks, which dump out the bottom via gravity. Marine holding tanks are sucked out through a 1.5" ID hose, which is smaller than the dump fitting in the bottom of an RV tank. So unless you can break up the sludge into pieces small enough to make it through the pumpout fitting and hose,Just breaking it up into chunks could cause more problems than solves.
That sludge is not only solid waste...it's a combination of waste, sea water minerals and salt, holding tank chemicals and prob'ly also dissolved TP (and btw, you need to check your head discharge hose for buildup in it). CLR would have a better chance of dissolving it than a stool softerner! In fact it just occurred to me that CLR might be worth trying if it comes in anything except a spray.
This thread illustrates why holding tanks should be thoroughly flushed out at least 2-3x season and especially in preparation for winter or other extended layup.
That only works to clean the body fats off the tank walls...and also requires a couple of gallons of liquid detergent in the tank. It won't touch sludge.
I take it that muriatic acid would work but falls into the "damage the system" category? Is there some level of dilution that might loosen things up that also would not be harmful? I'm guessing not or you would have recommended it.
Muriatic acid works to clean out sea water mineral buildup in the hoses--and won't harm the system when used as directed--but won't dissolve sludge that's turned to concrete. When it comes buildup in the toilet discharge line, like most things prevention is easier than cure: a cupful of undiluted distilled white vinegar flushed all the way through the system weekly, followed in about 45 minutes by a couple of quarts of clean FRESH water.
Now that's interesting. I have a Thetford 550P MSD that had some some sludge that turned to "concrete" and the muriatic acid made short work of it. In that case, though, I removed the entire porta potty and treated it separate from the rest of the boat's plumbing. (I did not have any significant build up in the hose from the porta potty to the macerator and from the macerator to the through hull.)
Really? That MAY be because unless you're filling the flush water reservoir with buckets of sea water, what you had was just solid waste that hadn't quite fossilized yet, no mineral or salt in the mixture. Since you had no mineral buildup in the discharge line, though, it's more likely that you're flushing with fresh. Whatever the reason, it's first time I've heard of muriatic acid working on "concrete" sludge.
Interesting thought that would never have occurred to me. But now that you've mentioned it, it's definitely a possibility on boat on the hard for the winter in MI. In that case, thawing it out by warming up the tank a bit might be all that's needed to soften it up enough to pump it out. Just warming up the boat with a ceramic heater should be enough to do the trick...he'd need power though.
I always and only use FW in the reservoir. It was definitely calcified-- kinda like shale. It had sat in the bottom below the pickup tube despite my running 3 buckets of fw through the system after each trip. I now rinse everything out more thoroughly and will keep a closer eye on it in the future. Fortunately, unbolting the whole thing and cleaning it out at home is not a major task.
The muriatic acid bubbled like a son of a gun and completely dissolved the sludge. I also used a smallish bucket of it in which I dropped the pickup tube still attached to the macerateor hose, which would have been a hassle to remove from the boat. Same result. I would have had to chisel it off otherwise.
What you had wasn't sludge, it was something called "struvites"--urine crystal buildup. They're rarely found in marine holding tanks because most marine toilets use about 2 liters of flush water, but they're very common in RV tanks connected directly below direct drop toilets because RV toilets use so little water--only barely enough to slide the flush down the "trapdoor" in the bottom of the bowl...which also describes how most portapotties are flushed. Prevention is simple: run a bucket of water through the tank (it can be sea water if your fresh water is in short supply) each time you pumpout or dump...or at least fairly often. You might also consider switching to Noflex tank treatment if you're not using that already.
But I learn something new every day, 'cuz I never would have thought that muriatic acid would dissolve "concrete" sludge OR struvites.
Interesting. Well, I did make it a habit of running a few buckets of fresh water through the tank after a multi-day trip, but I still got the "struvites" just the same. I plan to be even more thorough in my rinsing regimen in the future.
I have tried the Noflex tank treatment and did not find it effective for some reason. I've had better luck with Odorlos.
I used it through the RV vent line on my boat. Then again through the level sensor.
It will blast away like a pressure washer, or you can use a pressure washer thru any port or pipe you can access.
Jim...