Black water tank treatment

[JackLClark]

I know you folks have probably gone over this subject 100 times. But I'm new to the site and would like your opinions.

My black water tank is clean ie. no solids at the bottom, yet when it gets close to 3/4 full and the wind is right, I get odors from the vent pipes on top of the rig. Sometimes, the wind will blow the odor over the top and down the side of the coach where we sit outside.

I have a '91 coach with the "T" type vent tops. Was wondering if the weathervane type tops that move with the wind would be better?

Also, is there such a thing as a black water tank treatment that totally deleates the odor?

I'd appreciate any comments.

[wolfe10]

While there are plenty of companies who will take your money for products to add to your black water tank, NONE will make the smell appetizing. And many are harmful to the environment, particularly to septic systems.

The object is to have it vented such that the odors do NOT enter the coach. The "wind seeking" vents do work to better vent the tank out the roof vent-- creating a slight vacuum at the roof vent, such that odors are less likely to enter the coach.

Are you sure the source of the odors you smell is the roof-- that is unusual. That is where you WANT that tank to vent (vs inside the coach).

More common causes of odors in the coach are bad seal at toilet base or loss of water in the toilet bowl and broken or obstructed tank to roof vent. It could be loose at the tank end or have an insect nest at the roof end obstructing the proper venting of the tank.

Brett Wolfe

[tbutler]

Several thoughts on your problem.

First, I have tried a number of tank additives and we are currently using the odor control from 5 Star Happy Camper, http://www.5starhappycamper.com/index.html Over the last four years we have found their product economical and effective. We have tried several others but always go back to this product. Purchased in bulk it doesn't take up too much space for a year's supply. We pack a 6 month supply in two 40 oz. containers which are about the size of two TP rolls. We then order the 130 oz. size and refill the smaller containers as needed. The large container is stored at "home" which for us is my daughters home. No product will make the black water smell good but this product is very effective in our experience and it is friendly for septic systems.

I agree that you must have some kind of leak in the venting system or the tank. The fact that this occurs only when the tank is 3/4 full or more suggests that the vent pipe extends into the black water tank a distance of about equal to the top 1/4 of the tank. Once the level of the liquid reaches that level, the vent pipe will be blocked off. Resulting odors will find their way out through any weak spot in the system. This would be around the vent pipe, perhaps a bad seal on the vent pipe entry into the tank or a crack in the top of the tank. Such an escape route would be near ground level and would explain why you would smell the odor as you sit outside your coach. Hope this helps.

[kalynzoo]

I was having a significant problem with odor in this MH, and my friend was having a similar problem in his Dolphin. In SoCal a 110 plus day baking the MH is not uncommon. We both installed the weathervane duct on top. It has greatly improved the odor problem in both rigs. We both use formalin based thexford. Enzymes just don't cut it out here.

Also, regular dumping is a must. When our friends dry camp at the beach for a few days, it means 4 or 5 days without dumping, but the temp is by far lower, so no problem. Make sure you maintain water in the bowl, as that is a source of bathroom odor.

Good Luck. I'd get the spinning vent.

[Roodriver]

My, my! Formalin is a carcinogen and should be treated as such. Yep it will kill all of the bugs in your black tank and if you dump in a septic system or pond system, will also kill the beneficial bacteria in those systems. Formalin is a formulation of formaldehyde which is the pesky chemical used in paneling and glues in those famous FEMA trailers and probably our RVS. The stuff really is bad news.

I've had some guys tell me that RIDEX works well for them, but doesn't do dip for me. I have tried the purple, orange, white, liquid and powder stuff with poor results, so now I'll try the stuff Tom is using. Hopefully it works. If I could figure a way to put a fish tank bubbler in the tank and restore an aerobic environment, I think the problem would be solved.

[jimbrightly@worldnet.att.net]

We live in the Arizona desert and have never had a problem with heat-generated odor when we used good ole Thetford blue (we also have a wind vane vent cap). But you should also use an additive in your gray tank. We use a combination of Pine-Sol and fabric softener in the gray and no longer have offensive odors coming from there.

[billsistek]

My wife and I have been RV'n for over 30 years. We have owned 7 RV's which includes 3 class A motorhomes. We have never had a problem with any of our holding tanks. We are not Full Timers but we have spent months at a time on the road. We have traveled all of the lower 48 states plus Alaska, most of Canada plus Mexico and the Baha. The only reason I tell you this is so that you know I speak with experience.

One of my least favorite chores and I expect one of yours too is dumping the holding tanks. To that end I only dump when absolutey necessary. Now the Grey Tank I must admit I do dump more regularly due to number of showers and the amount of laundry and dishes that are washed. The Black tank on the other hand I only dump when it is full. I don't go by the gauges, I just look into the toilet when it flushes to see how full it is. Another way to know when you should dump is after the first or second burp that toilet makes when it gets almost full. I do this because it only makes sense that the more water in the tank the cleaner it will dump. I then rinse the tank and then dump the grey water to rinse the hose. Over the years I have always added a little deodorizer/liquifer to the tank. I have tried the blue liquids, powders, tablets, etc but have always found that we do not like the chemical odor they leave in the bathroom. Several years ago a friend of mine gave me a bottle of Break-Up, a product that I never heard of, to try and I really liked it. It did not have that strong odor like all of the others I have tried, it only had a slight baby powder smell. It also did a good job of breaking up the solids and the toilet paper. After I ran out of the product I could not find it in any of the RV supply stores, Wal-mart, etc. I then went back to the old standbys and sure enough here came the old familiar odors. Then one day while we were checking into an RV Park I saw a bottle of Break-UP on the shelf in the RV section of the camp store. I bought the bottle and copied the website www.conservationchemistry.com, off of the bottle and ordered it on-line. It comes in both scented and unscented. You can also use it in a diluted form to wipe down you countertops and sinks etc. I now buy the product on-line and keep several bottles as back up and the manufacturer even picks up the shipping charges.

Bill Sistek

F308863

[Guest Wayne77590]

This is a topic dear to my bottom!!!!

I also have not had a problem with odor. I use the blue or the green drop in powder packets. However, that is after I have flushed. Like many, I dump black, then galley, then gray. Before dumping galley or gray I do a back flush with the built in flush system. I have a clear plastic elbow that I can monitor the outflow. Not pretty, but necessary for me. After many, many minutes, I will close off the black valve while the flush is running, building up several gallons of water in the black. Then dump again. I am always surprised at what I observe. I do this a couple times, then I ask the DW to fill the bowl and flush the toilet twice. This is with the back flush still running and valve open. Again I am surprised at what I observe. I continue to back flush and close off the black valve 3 or 4 more times for 2-3 minutes and repeat. I usually end up with nice clear running water. I close the valve and let the tank fill for 30 seconds to 1 minute. Then I add the blue or green drop in powder packet. I also put in a cap full of CALGON water softener. (Yes, I have noticed a difference with the CALGON). Every time I dump I use this method, except for an overnight then I may wait until we stop for a few days.

I have heard that you can use Cascade or other soap products but I'm afraid of the sudsing action of such a product. I just vision running down the highway at 60-65 mph and non-fragrant bubbles emanating from the top vent - or worse!