i have 3 15" tsns i want another rtc to replace my old one that died...if i found a 5" rtc could it go with the 3 larger tsns? i have a 6" yellow bullhead in there also that the tsns don't mess with but i think that is because of the spines...should i have the rtc in a grow out before introducing it to the group?...i also was thinking about another hybrid of the 2 to replace my old one in the same size....thanx