Oh, forgot about giving a coral update.
After my early days of becoming 'King of the Coral Killers' I am more than happy to report real progress.
I have Torches, Euphyllia, Hammerheads, Galaxia (wavy things) that are growing well. One piece of a green Acropora type thingy initially looked poorly. It went from a bright green to a very pale colour. However, it has encrusted it's base onto the rock, and is now getting it's colour back. I suspect/feel/think that it put a lot of effort into the encrusting stage of growth, to give itself a solid platform, which caused the paling, and now that has been achieved it is starting to grow upwards and outwards again and the colour is returning. This may or may not be the right thinking, but it's what I think has happened. I have a Gonipora which is doing very well. Other SPS are all showing signs of good growth. One is a blue finger type SPS thingy, that snapped off it's plug base when I first put it in the tank. I left the plug base in the tank as it has a tiny bit of the coral still on it. That tiny blob has now grown into a good sized blob, and I use this as a growth indicator ! The Florida Ricordia is spreading well, and the Leathers are also growing well.
I think I've finally cracked my coral death touch. Initially, I think I 'chased the numbers' too much. I was a bit fixated on zero Nitrates and zero Phosphate, but I now realise that this was not good. I've also stabilized the Calc/Alk/Mag through rigorous testing and adjustment of the dosing, so that I now see only tiny fluctuations in these parameters. I use NOPOX to keep the Nitrates below 10ppm, and the Phos just stays stable at 0.02. Red Sea Colours ABCD are dosed just once a week, based on the Calc usage. I've also kept water changes down to a minimum. I think my last water change was about six weeks ago (or thereabouts).
I shall be sending off another ICP test this coming week, as I'm interested to see what the various levels are in the tank now.
