280 litre marine project

I set this tank up after loads of research and went down the route of a 4 foot tank rather than a smaller one simply because the more water you have the more forgiving it is. So many times I've heard folks start with a smaller tank "to get started" in my honest opinion it's harder to keep a small tank than a big one.
I don't currently run a skimmer on my tank but I change 25 litres of water every 4 weeks or so. Top ups are RO water but water changes are salted RO. Rather than mix my own salt water I buy it from John at Aqua Marine online in Middlesbrough. He charges me £5 for 25 litres and at that price it isn't worth mixing my own or installing my own RO filter.
I'll keep this thread updated with progress but for now here's the stock list.
20 kilos live rock
4 hermit crabs
1 emerald crab
3 false percula clowns
2 green chromis
1 cleaner wrasse
1 regal tang
1 sail fin tang
4 turbo snails