diff --git a/Dockerfile b/Dockerfile
index a142941..5869617 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -4,7 +4,6 @@ MAINTAINER Bartek Fabiszewski (https://github.com/bfabiszewski)
 
 ARG DB_ROOT_PASS=secret1
 ARG DB_USER_PASS=secret2
-ARG ULOGGER_TAG
 
 ENV ULOGGER_ADMIN_USER admin
 ENV ULOGGER_PASS_STRENGTH 0
diff --git a/README.md b/README.md
index 65a2fa3..f6492ab 100755
--- a/README.md
+++ b/README.md
@@ -40,9 +40,11 @@ Together with a dedicated [μlogger mobile client](https://github.com/bfabiszews
 - You may also want to set your new user as an [admin in config file](https://github.com/bfabiszewski/ulogger-server/blob/v0.2/config.default.php#L67).
 
 ## Docker
-- Run `docker run --name ulogger -p 8080:80 -d bfabiszewski/ulogger` and access `http://localhost:8080` in your browser.
-- Optional configuration options with ENV variables, for list see [Dockerfile](https://github.com/bfabiszewski/ulogger-server/blob/master/Dockerfile).
+- Run `docker run --name ulogger -p 8080:80 -d bfabiszewski/ulogger` and access `http://localhost:8080` in your browser. Log in with `admin`:`admin` credentials and change default password.
+- Optional configuration options with ENV variables, for list see [Dockerfile](https://github.com/bfabiszewski/ulogger-server/blob/master/Dockerfile). The variables correspond to main μlogger configuration parameteres.
 - For example: `docker run --name ulogger -e ULOGGER_LANG="pl" -p 8080:80 -d bfabiszewski/ulogger`.
+- You may also build the image yourself. Run `docker build .` from the root folder where `Dockerfile` reside. There are optional build-time arguments that allow you to set default database passwords for root and ulogger users.
+- For example: `docker build --build-arg DB_ROOT_PASS=secret1 --build-arg DB_USER_PASS=secret2`.
 
 ## Todo
 - improve track editing