[I had mangroves before. They are kind of cool looking - I planted them inside of my display tank (15 inch deep). Maybe growth rate seems slow - I thought they were growing fast. My double in size, from 10 inch to 20 inch in about a year or so. They put out alot of roots which are good hiding place for pods. I got rid of them eventually because they did not work for me in the display tank (which lacks deep sand bed). What I did was using two acrylic containers - filled with sand to grow Mangroves. The containers were restricting water flow - and cause algae to grow around the box.]