Holding tank buildup

B

Brian

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My boat is an 85 Chris . Over the years things have built up in the tank. When I get pumped out the stuff flows out but when I fill in up with water to rinse it only takes about 5 minutes and it is full. It is a 30 gallon tank so I would think that it is still more that half full with the waste. Any suggestions how to loosen things up and get it to empty more completely.
 
If it is a raw water flush, it's may not be waste that has built up but sediment from the flush water that is drawn in. I had the same problem a couple of years ago with my 1987 Carver. I actually ended up removing the holding tank and blasting it out with a pressure washer. Lots or sand, silt, mud and micro-beasties that were drawn in with the flush water had built up about a 2" layer in the bottom.

When I installed my Marine Elegance head I switched over to fresh water flush so no more problem.

Bob
 
quote:
Originally posted by Brian

My boat is an 85 Chris . Over the years things have built up in the tank. When I get pumped out the stuff flows out but when I fill in up with water to rinse it only takes about 5 minutes and it is full. It is a 30 gallon tank so I would think that it is still more that half full with the waste. Any suggestions how to loosen things up and get it to empty more completely.
Click to expand...

Since the outlet of the tank is at the bottom, I don't see how it could be half way full of waste and still be able to be pumped out. There might be some buildup in the corners, but not fifteen gallons worth.

Timing how long it takes to fill it with a hose will not tell you how much water is being put in unless you know the flow rate. If you want to test the capacity, pour water in by the gallon and count how many gallons it takes.

If you think you need to clean the inside of the tank, by far the best way is through an access plate in the top of the tank. If it doesn't have one, you can install one if the tank is accessible.
 
If the hose is turned on full it should put on about 5 gal. per minute, my hose at home puts out 6.5 gal. per minute. So maybe your tank is not so bad.
 
If you have access, empty several large bags of ice cubes into the tank; then take the boat out into choppy water and give it a good workout. Change speeds, lots of sharp turns, etc. The ice cubes will scrub away during this process.

Then when you get back, do another pumpout and see how much junk comes with the melted ice/water.
 
+1 to Flutterby. Add a some Calgon as well. It softens the water left by the melting cubes as well as the build up. I have found both aid in the cleaning process. I dump liquid calgon in the tank after every pumpout. So far, so good.
 
"Calgon, take me (and my poop) away!" :-)

I've heard Liz's suggestion before and the results were positive. It's worth a try considering how affordable ice is.
 
When I redid my system I had the built in hull tankapart to reseal the lid and found a tremendous amount of sediment.

I did not expect to see this as this is a factory fresh water flush vacuflush system

I regularly add something to keep this from happening again.

I have used dishwasher soap and have added pine sol from time to time.

I also regularly add liquid kitchen soap like Dawn to the head to keep things clean.

Don't know if it helps, but it can't hurt.

RWS
 
quote:
Originally posted by RWS

I regularly add something to keep this from happening again.

I have used dishwasher soap and have added pine sol from time to time.

I also regularly add liquid kitchen soap like Dawn to the head to keep things clean.

Don't know if it helps, but it can't hurt.

Click to expand...


If you are using a biological odor treatment like K.O. or Odorloss (the one I use), this will hurt. It will kill the organisms that digest the sewage and control the odor.

If you're just using a chemical treatment to mask the odor, you're probably fine.
 
I expect a certain amount of sediment regardless of the system used and the source of the water. Scat ain't exactly liquid. Regularly flushing after a pump out is always a good idea. The problem with that in the Bahamas is the water is expensive.
 
I cut an access port in the top of my holding tank. Why? Because I bought a tank level monitoring system that uses plates stuck to the outside of the plastic tank to monitor the level and they wouldn't work because of residue (of you know what) stuck to the tank walls.

Anyway, the boat was eight or nine years old at the time and had been used extensively for cruising by the previoua owners. A lot of waste had passed through that system. When I looked inside, there was no more than 1/2" or so of sludge on the bottom and perhaps 1/4" at most clinging to the sides.

As I posted above, if there was more than an 1nch or so in the bottom, it would be impossible to pump the tank out because the sludge would cover and block the tank outlet.

For anyone whio is anal (pun intended) about keeping a clean holding tank, RV stores carry a device that's installed in the top of the holding tank. City water, under pressure, is connected to it and it rotates much like a lawn sprinkler to rinse the inside of the tank after a pumpout.

http://www.campingworld.com/browse/products/index.cfm?prodid=4969&green=2E6907C2-CD31-5D4F-B066-8D62329707EC&rewrote&cartsrc="WEBREC
 
NO $HIT !

(sorry, I just could not resist and wanted to post it before anyone else beat me to it !)

RWS
 
Ron, now that sounds like a good idea!!! I've never heard of adding Calgon....but I used to use Odorloss all the time between pumpouts with great success.
 
First thing to do is find your holding get a flash light thats got a bright light. Put the flash light against the holding tank and you can see inside of it. When you put fresh water in your tank let it flow with a slow stream. Also you might have a odor vent on your vent line that might be clog. If you put fresh water in your water tank at full force from a hose it will do the same thing.Water will shoot out thinking the water tank is full. It will be 1/4 way full youneed to put in slow.
 
quote:
Originally posted by JimPend

If the hose is turned on full it should put on about 5 gal. per minute, my hose at home puts out 6.5 gal. per minute. So maybe your tank is not so bad.

Click to expand...

Not only will the local water pressure affect the gallons per minute rate, but the length of the hose will affect it.
 
I use KO after every pumpout.

I recently heard about this product Noflex Digestor
It supposedly will clean the tank, where KO just keeps the bacteria well fed!
 
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