Drilling the tank.
Since I had never drilled a tank before I figured I’d practice a little first. I purchased an appropriately sized diamond drillbit from E-bay for roughly $40 with shipping. I had a practice run on my old sump (which will probably become my daughters tank when she’s ready.
It took quite a while to do it – but essentially, it was rather easy to drill. I knew the 90 would be more difficult since it’s about twice the thickness – but I figured it would be a breeze.
It was.
I drilled 2 1†holes in the middle of the back pane for the intake of the closed loop. In hindsight, I could have drilled all of the returns too – but, no regrets.
In hindsight - painting AFTER you drill is better. As you can see it chipped a little. Nothing a little touchup can't take care of.