ok thanks. i have a 220L 3ft and 220L 4ft. the 4ft is narrow maybe about 40cm wide which is why its the same literage as the 3ft. i was planning on putting them in the 3ft, which is indeed densely planted. I have already got 2 apistos, ive been told they are the macmasteri pisto. they are in a planted 20L holding tank, until i transfer them to the 3ft. i was planning on transferring all the fish at the same time?