I have a clarity plus acrylic tank dimensions are 72"L x 24"W x 36"T 265g with around 50 African cichlids Hap/peacocks. Tank is 3/4 thick including top. I purchased it used around a year ago, everything is going great. The only complaint is that there is only on one overflow and it is at one end of the tank. I have a eshops 300g sump mag 24 as a return pump and two Koralia circulation pumps, one 750ghp and one 1400ghp. The top of the tank has two large access panels like most acrylic aquariums, but only one small hole on the opposite end of the overflow for the return lines and wires to the power heads. I would like to drill two holes in the top of the tank one centered in the back and one on the same side as the overflow. I plan on adding an fx5 as my haps are starting to get large and you can never have too much filtration.
I made a quick ms paint sketch (nothing is to scale or symmetrical) everything in black is original, the parts in red are what I want to add. My question is should I drain the tank 25%? 50%? 75%? Any advice would be great. I plan on taping the top and bottom with painters tape and attaching a container under where I am drilling to catch the shavings.
Thank you in advance,
Josh

I made a quick ms paint sketch (nothing is to scale or symmetrical) everything in black is original, the parts in red are what I want to add. My question is should I drain the tank 25%? 50%? 75%? Any advice would be great. I plan on taping the top and bottom with painters tape and attaching a container under where I am drilling to catch the shavings.
Thank you in advance,
Josh
