A simple method that normally helps is changing your substate to aragonite sand with at least a 2" layer. This should buffer your PH to 8.2 and replemish your calcium levels.
Did you get your other tests?? what was the readings ?

Bristle worms can be trouble when they get large....so if you want to make your own home made trap...which I find really fun using...heres a link which describes how to make one pretty cheap but effective.

http://netpets.org/fish/reference/reefref/bristle3.html

A very good sand would be a Aragonite Reef Sand - companies do various sizes from 1.2mm white like Natures ocean.
I normally place a 1" miracle mud base on the back half of my tank then cover the rest of my tank with 2" aragonite fine sand which does very well.
Aragonite will help buffer your PH to a min 8.2
But if you are using a fine sand - do make sure that your water current is good and that you have a sand shifting goby like the Chalk gobies.

Yes you can break up your own existing LR to make LR rubble - shops normally just sell the broken bits at a cheaper cost.

Your lighting and current sounds fine - have you gently shaken your coral to see if any sand got trapped within its tissue??
If your coral did roll around while being transported home - these corals can be damaged very easily as they do have fine delicate edges that can be easily broken - which can lead to infection. So do keep an eye out.

There are a few checks you will need to do before we worry too much.
First - is the current too strong?? LPS corals do need a nice gentle current - but if it is too strong..many will not be able to open up.
Second - Lighting - what lighting do you have? maybe move the coral higher??
Third - on transportation or when you placed coral into tank - did you get any debri like sand into the tissue to irritate coral....double check by very gently turning your coral upsidedown and shake it....gently.

You just prolly didn't prep your filter correctly so a air pocket got trapped.....your filter is just getting rid of the excess air. At best they air will get filtered through...at worst...the air pockets can damage your filter.
If worried - just re-do your filter making sure no air is trapped inside.

Hi,
Would really need a pic as there are so many species of snails many are good but there tends to be alot more not so good snails out there.

BTW..the reason why your dove snails are doing so well...you must have lots of algae for them to feast on lol.....they will eat almost any pest algae and keep your tank pretty clean if you have enough of them....so no....they are not a pest...far from it

Hi Dion
Glad you got those flatworms under control..and I do agree with you..if you are happy to siphon them out every so often..then avoid doing a fresh water dip as I only use this method as last resort.
As to your new life popping into your tank - the first looks like a dwarf red bristle starfish not unlike Axiognathus squamatus - they can over run your tank if you overfeed so are good indicators to your feeding habits. So do keep an eye out on the numbers..but they are safe in small numbers...they only become annoying if they multiply to silly numbers and get in between the LPS corals...their wavy arms prevent the corals from opening their polyps fully.

The second pic is of Botryocladia skottsbergii a red type of bubble algea which is considered a pest..but I like them they will grow into what looks like a bunch of grapes. Under the right conditions this algae can multiply rapidly - this is more true of the green species. So you can decide for yourself if you want to remove them now. Best method is to take rock out of tank - take a sharp screwdriver and pry them off whole - DO NOT burst the bubble as the spores are within the bubble. As I said...I liked mine and as long as your nutrient load is low...they are not much of a problem....if you see the green bubbles Ventricaria ventricosa..I would remove those asap as they do grow uber fast and not so cute as the reds.

The third pic is off my favourite snail....dove snail....love these.....I consider them better then turbos as they can correct themselves when they tip over...they can glide over sand and get into all the small places eating only algae without knocking over corals....and the best thing....they can breed in your tank. You will see little tiny looking petri dishes on the side of your tank glass - inside these 8mm dishes....there will be 2-8 eggs which will develope into mini snails....freebie cleaner crew. Lucky you got rid of wrasse as this is one of their favourite snacks.