Having some mana issues with my Priest

So was running Throne of Tides last night for the first time.

Currently my team is lvl 82, Running with Pali, Priest (disc), mage , shaman x2.

Still working on movement and such, so I did take way to many water spouts, and getting out of the poison puddles was a bit slow.

That said, was lumbering my way through the fight and ran out of mana on my healer with the named at 40% or so, it was late and was tired, so figured I would start up again today.

Currently my priest is at 46k mana, and has 771 regen (with no group buffs).

I'm sure when I stop sucking so much and avoid the water spouts better things will be easier on my mana, but think I've also gotten sloppy with my healing in wrath.

Looking at mana costs it seems Flash heal really shouldn't be used if mana will be an issue, (think it has become my spam spell so will have to retrain) Renew seems ok mana wise but not as efficient as I would have thought. I keep PW:S on the tank. Looks like Prayer of Healing is what i should be using to heal up the team, have in the past just healed those that needed it.

Any one with Priest healers have any suggestions?

Flash is your oh shit spell. Spam Heal, use Greater heal for large incoming damage amounts.

Well went back today, and it was amazing what avoiding the water spout does for required healing hehe.

Killed her first time back today, even with some spastic targeting on second set of add. So that was the biggest help to my mana,

Also as you mentioned, not casting flash heal anymore unless emergency, and moving heal onto my healbot clicks as well.

Do folks use power shield much on non tanks? I was reading up on the power proc, and noticed it says only 1 every 12 secs but does seem to have okay efficiency.

PW: Shield is pretty decent, if you're a Disc healer.
You can make it a lot better than the default spell - have it heal for a small amount, protect for a lot more, damage opponents as they break through it (threat free), and give you fairly substantial haste on your next cast.
And it is instant cast, so less mana, etc.
Fits in with the whole idea of mitigating income damage instead of healing after the damage has been dealt.

For Holy, it is another tool in the arsenal.
But much less useful.