Not to hijack the thread, but I too am curious as I just picked up a 5 inch male dovii and am planning on keeping it in a 75 until I move it to my 125 then I will eventually get a 210. I have seen that people say the minimum tank size for dovii male is 180 gallons at full growth. But, I have also read that they reach 12 inches in the first year but take several years to reach 18-20 inches. If that is true then a 125-150 gallon tank should work for a few years for a solo male. I will be curious to what others say on this.