There may be more detail about the spray bar in my 12gal journal.
It's rigid tubing. Its OD is the same size as the ID of the tubing I'm using. You can buy rigid tubing from most fish shops/pet stores and online.
Just a plastic cap that fits over tubing.
Holes are less than an inch apart, some going slightly up to agitate the surface, some going slightly down for water flow. The amount of holes, distance, size, etc really depends upon the filter you're using and how much flow you need. For me, I just did a trial and error thing with the filter.
Could you share some info about your DIY spraybar?
Like, what kind of tubing is it? and what did you use to cap the end?
How many holes, and what size drill bit?
I am really interested in building my own
Edit: just read that it is made out of rigid tubing, is this something I can find at menards/lowes/homedepot? and do you know if it comes in any color other than clear?