Tank drilling time!
TOOLS!
I order both holesaws off ebay, bought them both for about 20 dollars canadian (free shipping
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The goal of drilling the tank was to allow me to add a closed loop. I drilled all four holes on the bottom pane (intake/exhaust). I chose the bottom pane, because it was drilled previously for the overflows, so i knew it wasn't tempered and I did not know the type of glass on the rear panel.
I'm not overly concerned about the intakes to sucking sand or anything else since the tank will be barebottom.
I drilled 2 holes for a 1.5 inch bulkhead and 2 holes for a 3/4 or 1 inch bulkhead.
I chose to drill 1.5 inch intakes because the super dart requires a 2 inch intake. And if the flow is reduced at one of the intakes the pump preformance would be impacted less.
Pics of pump
The drilling went very well, no major issues. In fact each hole was drilled out rather quickly, faster than i expected. I watched videos online before drilling, i found the basic technique for drilling which worked very well.
The holes which concerned me the most about this project were these ones.
They are the holes in the overflows, four of them in total. They were originally drilled with odd sizes. In fact the previous owner just used male/female threaded fittings and used and crap load of silcone.
They concerned me becuase, I wasn't sure how they would react with re-drilling, and because how close they are to each other. I thought they might explode or crack or numerous other things.
My other conern was with the larger hole, I wasn't sure i would get enough clearance from the overglass for a 1.5 inch bulkhead.
Fortunately they drilled fine, they were a little harder to start, and i went slower with drilling them. And after drilling I did a test fit of a1.5 bulkhead and a 1 inch bulkhead, both fit prefectly.
The overflows will contain one 1.5 inch overflow each. One 1 inch return in the right overflow and a 1 inch emergency overflow in the left.