Echino growth

[bromion]

I have a lovely blue Echino that's about one inch in diameter. Had it for 6 months or more, and it has not really grown in that time. It seems healthy, but no growth. I am keeping it on the sand bed and don't directly feed. My lighting is 2x250W 20kK MH. Any tips for getting it to grow more rapidly?

 

[All Delight]

For me they grow slow, and once they get comfortable and stable they take off. Like don't move then all the time or touch them or let them get stung, etc.