I’m actually starting to find that out, I’m torn between 10s or 20 Longs. Petco has their $1/gallon sale in my area so I was going to get them there.
I’m leaning more and more on air driven filtration so I don’t have to drill all those tanks and risk breaking so many of them. I’ll just have to find some quality budget heaters for all the tanks.
Also consider a rack for a couple 75s or 125s and just using dividers to make separate growout chambers. That would help with the heater problem and simplify filtration as well.