i have stylo's i have kept them for a long time if an sps is getting to much light it will bleach out if your stylo is skinny and brown that means not enough flow and you may have a alkalinity problem if they are browning. It is very hard to keep sps in a small reef system because the water...
You can fix that tank you have to drain it first and have some epoxy brace rods from front to back of tank on the top of the tank which should have been there to begin with the glass is to thin and it needs brace rods to support that bow effect