Since it is just water, it should go directly to the laterals. If the septic tank was full, the toilet would not drain. There may be a problem with the tank or the lateral field.
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Put simply a septic tank is always full!
It starts off being full of water.
Over time (a long time) a layer of processed toilet forms at the bottom as compost.
At the same time the lighter than water items, grease,fat, oil, plastic etc: float on the top.
Our toilet is 70% water, the remaining 30%solids are converted into carbon dioxide and methane gases before dropping to the bottom of the tank as a few grams of compost, hence the fact that a correctly sized septic tank , used only for things we had already eaten, will take twenty or thirty years before it requires emptying.
As waste enters the tank, it pushes processed liquid out of the other side.
The level remains the same.
All this stops when the drain field is full of liquid, due perhaps, to a raised water table, if your drain field is sitting in the middle of an underground lake, then you have to wait for the lakes water level to drop, before your drain field will empty.
A company should not install a drain field where there is less than 36 inches of soil between the bottom of the drain field and the seasonal high of ground water.
You need your septic tank cleaned out.
This all depends on the condition of the septic tank. Its like asking, how long is a piece of string
Ideally 1/4" per foot minimum
Performing routine septic tank maintenance will prevent your septic tank from backing up and flooding your yard. If a septic tank backup happens, it could cost you thousands of dollars to fix. Use a septic tank kit that you can pour down the toilet once a month. It will contain the necessary enzymes needed to breakdown solid waste material inside the septic tank, keeping fluid flowing freely through the drainpipe. Avoid disposing of materials such as Q-tips, tampons or excessive toilet paper, as these items will clog your system and are hard to break down. Consider using septic system safe toilet paper.
If you really mean it flushes but the water does not run away, then the septic tank is plugged.
wrong stuff placed in the toilet
You need your septic tank cleaned out.
Yes, -but the tank is filling up and will soon overflow starting at the lowest toilet. Much easier to service or replace your septic pump .
The overflow tank is either cracked or its overheating and leaking from the cap
That would depend on how far it was to the septic tank.
adjust the floating bulb, it may be running over the top of the overflow pipe
Either the flapper in the bottom of the tank is leaking or the water level is too high and it is running down the overflow tube.
This all depends on the condition of the septic tank. Its like asking, how long is a piece of string
An RV toilet is designed to be mounted over a holding tank. They use almost no water which at first might sound appealing, but unless you have a septic tank under your bathroom it would be bad news for home installation. Unless modified, an RV toilet would not be able to get the solid waste to your home septic system. A home toilet uses the force of the water to move the solid waste to your septic tank. Look for a low flush toilet or a composting toilet instead.
Ideally 1/4" per foot minimum
You need an upflush toilet.
An overfilled septic tank can cause backups in a sewer line, causing many problems in a plumbing system. If a septic tank has overflowed, it is usually clogged with excessive organic debris. A septic tank cleaner can be a good first step when treating a septic tank overflow. Septic tank cleaners contain natural bacteria and enzymes, designed to break down organic material in human waste. Excessive disposal of bleach and detergents into a septic line can kill these bacteria, preventing the breakdown of septic waste in a tank. If a septic cleaner doesn't clear a tank after a week, it may be necessary to use a professional septic tank cleaning service.