slow drain of freshwater tank

[dgtjhatt]

Recently purchased a class c and everything works fine except now I have a very slow drain when I try to drain the freshwater tank. I'm wondering if the last owner left water in the tank to long and their is a build up of algae in the tank and it has clogged the drain lines. I tried to run a wire thru the drain line but there are two elbows that the wire won't go passed. Is their something to put in the tank that will help clear up this problem?
Thanks for any suggestions you may have.

[lane_hog]

Doh... read fresh and thought grey.

[DrewE]

lane hog wrote:
Something else to consider... Grease and oils from the sink and shower will congeal and line the drain pipe. Running some very hot water thru your empty tank and into the drain line can go a long way towards restoring flow in the grey line.

That's reasonable advice in general; but it isn't a lot of help for a slow draining fresh water tank.

[lane_hog]

Something else to consider... Grease and oils from the sink and shower will congeal and line the drain pipe. Running some very hot water thru your empty tank and into the drain line can go a long way towards restoring flow in the grey line.

[klutchdust]

Anyone use these? I made a wand that I connect to a hose and insert into my black tank when emptying . It produces a nice multi angle spray and with a few capfuls of dawn a nice foam quickly appears. It's eliminated all odors and I find that just "spritzing" with a bleach based cleaner after each drop that i haven't found the need to use tablets.

[Rick_Y]

bobndot wrote:

I had access to the top of tank which was under a bed. I cut a large 8" hole in the top of the tank to allow me to reach inside.
I removed the cut out plastic parts and cleaned the tank by hand. I sealed the 8" hole using a marine deck plate. In the future, all I have to do is unscrew the deck plate and reach inside to clean.

Great idea. Thanks.

[bobndot]

Sometimes when they cut out a hole for something they don't remove the plastic part that they cut. They let it drop into the tank and that will possibly block the drain.
I had access to the top of tank which was under a bed. I cut a large 8" hole in the top of the tank to allow me to reach inside.
I removed the cut out plastic parts and cleaned the tank by hand. I sealed the 8" hole using a marine deck plate. In the future, all I have to do is unscrew the deck plate and reach inside to clean.

[enblethen]

Any debris is now back in your tank. It will come back!

[dgtjhatt]

You guys are all great but the winner is (ltsyrv). You were right. The simple thing worked the best, a shot of compressed air. That's why you make the big bucks!
Thanks Again!

[ItsyRV]

If this is just a straight full gravity drain, you can try and shoot some water from a hose backwards into the line. Maybe even a shot of compressed air. There are commercial fresh water tank cleaners that uses relatively safe compounds to remove algae and sludge from the tank and lines.

[enblethen]

Your rig ?
Can you access the connection to the tank? If so there could be drill filings that is obstructing the outlet and could even be in the 90s you referenced. Only way to clear them would be to get to them.
Adding 1/4 cup of bleach for every ten gallons of tank volume would sanitize the tank. Running the pump until you smell and feel bleach in each faucet would sanitize the fresh water plumbing.
It is a good idea to sanitize the system each spring before use.

[Lwiddis]

Fresh water tanks drain slowly compared to waste tanks. Do you leave a faucet open for air?

[suprz]

A smaller diameter more flexible snake? Or if it's accessible, get right to the fitting at the tank to take drain line off? Etc... First thing I would do is get that tank some bleach or whatever kind of disinfectant you want to use to kill that algae