I want to install a toilet in my basement I want to connect it to the pipe going to the septic do I need to install a vent or can the existing one handle the third toilet.

Can you take pictures or draw up a diagram that shows us where the old fixtures are located and the new toilet in relationship to the vent? Regards, Tom

Also tell us abit about your septic. Does the sewer pipe run staright to the tank all under ground or do you have a 4' pvc goose neck sticking up in your yard.

Can you take pictures or draw up a diagram that shows us where the old fixtures are located and the new toilet in relationship to the vent? Regards, Tom

No problem ill take the picture and add it


Also tell us abit about your septic. Does the sewer pipe run staright to the tank all under ground or do you have a 4' pvc goose neck sticking up in your yard.

It's a 3" pipe that goes straight to the septic and a pipe sticking out in the yard near the tank


no problem ill take the picture and add it

Here's the pic

Don't think you are going to be able to use a standard toilet, you need a Saniflow or up flush. You sewer drain leaves the house above the basement floor grade

What you have pictured doesn't look like a vent to me. It loos more like the house drain leaving your house.
Bob's bang on! You'll need a up flush unit such as Saniflo, (see image) to install a toilet in your basement. Good luck, tom