I stocked my 125 gallon with some green fire tetras and it doesn't look like enough. I put in around 25 and they don't usually school together. I am thinking about putting in more but I'm not a fan of overcrowding. I have a medium to large rhino pleco, 7 small corys, 2 small bristlenose, and a banjo cat along with the green fires. I am using am Eheim pro ll 2028. All the tetras are an inch or so. could I fit like 25 more? 50 more? 100? I can always add a sponge filter to help filter and move water. what do yall think.