Blank Tank Stinks

pvarady1

Member
RV LIFE Pro
Joined
Nov 4, 2014
Posts
16
Location
Bowie, MD
I have filled and drained my black tank several times but after putting new enzymes in it it still stinks. What type of deodorizing enzymes do you use to keep the smell down. I also have issues with the kitchen sink. Can you put baking soda down the RV Kitchen Sink to help with the smell?

Any ideas are welcome.

Thanks!
 
We have been using Camco TST for a good while now.
We also pour some in the gray tank as well.
Works well for us.
 
For the gray water tank Camco TXT gray water treatment helps. Using only Dawn soap in the kitchen and lots of water will help keep from grease buildup in the tank.

Your black stinks because there is residual waste still left in the tank. It will always be a problem if your toilet is on the right side of the coach. Make sure the toilet bowl is always clean. Fill the toilet bowl partially with water before using. Lots of water during flushing. Finally use a Valterra Master Blaster rv tank cleaning wand periodically to ensure the black tank has no residue. In my coach, I find the factory installed tank flush works well, if I first fill the tank half way with clean water using the toilet and bathroom sink and empty it. I think it helps to fill the black tank with about one inch of water after cleaning before using it again.
 
I don't think there's an overnight fix. Here's what I'd suggest. It's worked for us:

Gray tank:
Do not put any food items down your sink drain. Take the small extra step of using wet wipes to remove food from dishes, then throw away with trash. NEVER put grease down your drain... you're just asking for a nasty stink! Think of the sink washing as a sanitizing step. That way only soapy water goes into your gray tank.

Black tank:
Starting with a WELL FLUSHED tank, put about a cup of any liquid laundry detergent + about 1/2 cup of liquid Calgon. Any detergent will do, and any type softener ("slickener") works... Calgon was always our choice, but is getting harder to find. You DON'T need expensive proprietary stuff unless it makes you feel better.

Then (IMPORTANT!!) add about 5 gallons of water to the tank. Yes it takes away from tank capacity, but it's a necessary evil if you want to avoid stank.

As you drive the detergent will slosh and coat the interior of the tank. As you add poop to the tank, it will mix with the detergent solution.

When it comes time to dump the black tank, drain it completely. Then fill it at least 3/4 full with water. Dump. Repeat.

Then add the detergent/softener and 5 gallons of water as before to start all over again. Your gray tank doesn't need any special treatment IF you get all the rotted food remnants flushed out.

These steps DO take a little extra time and effort... anything worthwhile always does. But your tank "stank" will be a thing of the past!
 
I have filled and drained my black tank several times but after putting new enzymes in it it still stinks. What type of deodorizing enzymes do you use to keep the smell down. I also have issues with the kitchen sink. Can you put baking soda down the RV Kitchen Sink to help with the smell?

Any ideas are welcome.

Thanks!
Couple gallons of water and some of this pine saw
I have filled and drained my black tank several times but after putting new enzymes in it it still stinks. What type of deodorizing enzymes do you use to keep the smell down. I also have issues with the kitchen sink. Can you put baking soda down the RV Kitchen Sink to help with the smell?

Any ideas are welcome.

Thanks!
Couple gallons of water and some of this pine sol knock off!
 

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I have filled and drained my black tank several times but after putting new enzymes in it it still stinks.
Does it stink inside the RV? If so, check that the tank vent is not blocked. There should be a vent outlet in the roof. Make sure birds or insects have not built a nest there.

The sink drains should have a P trap that prevents odors from coming up into the RV. It's possible that driving has allowed the water in the P trap to get sloshed out. Run some water down the drain(s) to make sure the traps are full. The toilet depends on the seals in the drain valve to keep odors out. These seals can degrade. After opening the valve to flush the toilet I add a couple of inches of water to the bowl. This backs up the rubber seals to prevent odors from getting in. And if the toilet does not retain this water for hours/days then the seals likely need to be replaced.
 
I have filled and drained my black tank several times but after putting new enzymes in it it still stinks. What type of deodorizing enzymes do you use to keep the smell down. I also have issues with the kitchen sink. Can you put baking soda down the RV Kitchen Sink to help with the smell?

Any ideas are welcome.

Thanks!
Your kitchen sink is probably a leaking Air Admittance Valve (AAV) under the sink. The trap in the sink should prevent any odors from escaping the tank. Same for the bathroom sink,

The only time you should smell black tank odors is when you open the toilet dump valve. You do keep at water seal over the toilet ball valve?
 
I have filled and drained my black tank several times but after putting new enzymes in it it still stinks. What type of deodorizing enzymes do you use to keep the smell down. I also have issues with the kitchen sink. Can you put baking soda down the RV Kitchen Sink to help with the smell?

Any ideas are welcome.

Thanks!
For your black tank, One of the things that I do is pour a couple bags of ice down the toilet and take her for a drive. The jagged edges of the ice will slosh around and help clean the sides of the tank before it melts away. Also check that nothing his clogged the vent on the roof.
 
If you have a washer/dryer, run it for a wash cycle. Every time we’ve had odor, it was the GRAY tank due to the p-trap for the washer going dry.
 

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