Hello I have had this cactus for approximately 4 years. He is basically a square with areole on the corners and goes straight up. Please see pictures. I will try and describe him in very layman terms...to hopefully help identify him based on his habits. Sorry for the long post. In the first year he was really small, about 3-5cm tall and 1cm wide(in a width x length square) Second year he grew to about 10-12cm tall and 2cm wide, i forgot to water him for a long time and he got sun-burned everywhere. Third year: new growth. Feeling, guilty, I watered him a lot more regularly. On top of the sun-burned trunk, out grew a fat, fast growing square chunk. This chunk eventually got so fat and big and heavy that I decided to lop it off lest the plant falls over. I felt bad, and stuck the new growth in a new pot. The new growth was about another 12cm tall and 3.5-4cm wide. Fourth year, I now have 2 plants. The original plant stayed dormant for a while after the operation, then out of one of its four corners, came a bulb, which grew to be tubular and SIX cornered! This bulb continued to grow for 8 spikes, or about 5cm, then two of corners stopped producing leaves, and the plant became square again. It is now late summer, and the plant has become 45cm tall and 3cm wide. Good year. The second, new plant, kept growing as well. At around 31cm he grew fat, then at 52cm he shrank back to original width. He is now 74cm tall!! So basically the new, non-sunburned plant grew 62cm in 9 months..... I'm hoping to get them identified, to see how tall/big they will get, and perhaps proper care information. I am worried all the time that they will topple over soon =( Thanks for any help
