Topic: Quick question about electrolisys rust removal. Black Gunk?

[Jinsonphoto]

I apologize if this has been asked before, but i just cannot find the answer. When doing the electrolysis rust removal on a tank what do you do to remove the black gunk left over? I would think bb's or rocks would work, but if there is another preferred method Id rather find out before experimenting.

Thanks in advance!

[greenjeans]

Was the tank cleaned first ?     When I did mine there was only clean, bare metal left.

Is the black junk leftover varnish/fuel etc ?      There could be rust under the gunk still.

[Jinsonphoto]

Well actually it's not finished yet. I did it for 24 hrs then cleaned the anode & I'm getting ready to check it as its gone 48 hrs now. Maybe there won't be any black gunk. There was after the first 24 so I assumed it would be a byproduct of the rust removal process.

[Rodger]

I am pretty sure after electo.... the old rust areas will have that black color to them too.  The black gunk will wash out with soap and water, rinse with clean water, and then I WD40 the inside to stop flash rusting.  I've done that method one time, I prefer acid which works fast but can mess the paint up if your not careful.  Side note the battery charger has to be an old school one, many new chargers are too smart to send voltage to this setup.

Cheers!