
Google puntius denisonii barb, you will find lots about the lovely fish you have. Some sites say 4 is fine, others say 6 or more....They reach 6" and need cooler water than most tropicals, and fast flowing water, high oxygenation. So you will want a good powerhead.
IF my finances improve in the next few months, I hope to add some to my 125 gallon tank. I currently have 2 balas, one 8" the other 10".
Your tank is not overstocked now, I just was cautioning you from getting fish that will eventually reach 13" as you will love them, and be FULLY stocked, with no room for another pleco. When you reach the stage where you are pushing the overcrowded point, your algae will become a problem, that is all I was pointing out.
You may just have to add a 180 gallon tank, then you could have your Roselines in one, and the balas in the other!!!
