Thanks all, really pleased with the whole tank at the moment. Starting to get some nice fish as well, the PBT is going great, and recently put in a long nose butterfly (lovely fish). A new clam and plating acro as well.
No secret KM. learn as much as you can, talk to the people on this board, buy the best equipment you can afford, and wait, wait, wait. All of a sudden things will click, and the tank suddenly comes of age.
2 bits of equip that made a difference were the streams, and the calcium reactor.
.....and lots of maintenance, water changes, etc.