slow leak into septic tank

[brando913]

Im having a slow leak into my septic tank. I had it pumped today and see the water dripping from the inlet tube. Its a slow but constant drip. Heres what Ive done so far to trouble shoot.
1. Checked all toilets: None running. I turned off all water valves to tanks and even sucked water out of tanks to make sure there was none seeping under flapper valves.
2. checked all faucets- no leaks.
3. Turned off main water valve at hot water tank and checked meter at the street. meter was not running so Im guessing the leak if from inside the house.
4. The only thing I can think of is that its coming from the hot water heater since its under pressure. Could this cause a slow leak even if water is turned off to toilets? I realize the hot water does not run to the toilets but would the pressure from the tank cause a leak into the septic tank? Could the small expansion tank that is attached to the top of water heater cause the leak issue?
5. I opened the relief valve on the water heater to see if this would stop the drip-no luck.

Any suggestions on what to check next would be a HUGE help!

[johnjh2o]

Do you have a RO filter? To check the toilets put some food coloring into the tanks and let it sit. If after time the coloring appears in the bowl you have a flapper that needs to be replaced. Also depending on the amount of pitch on the waste lines it could take some time for the waste lines to become completely dry.

John

[phishfood]

It is most likely to be residual water from the drain piping. Even with properly pitched, brand new PVC pipe, which has a really smooth interior, it takes a surprisingly long time for all of the water to drain out. If you have piping that does not have proper fall, is cast iron, or clay, or has some deposits built up on the pipe walls, it could take a really long time to quit dripping.

[brando913]

John,

Im not sure of my filter type but I do know we pulled it out of the tank when it was pumped out. The septic guy cleaned it off and said it was fine. I'll try the food color test on the flappers. Thanks for your reply.