Brand new iPhone took a swim.. Advice?

There are several options and a few ways you can approach that:

From a technican view I say: If your waterdamage is fresh (no longer than 1 Week) it can almost ever been saved. Time is the most important thing when it comes to water.

1) bring it to a shop that are known to deal with waterdamaged phone (sadly many provide that service but few know what they are doing) who can clean it professionally

-> this involves removing the EMI Shields (they are soldered to the logicboard) and a ultrasonic cleaning with sweeping frequenzy and a manual cleaning corroded spots

then they need to figure out what parts needs to be replaced (hardest part) and of course replace them. Every waterdamage repair should come with a battery replacement.

If they do this properly, you can be happy for many years with that phone.

To answear your question: YES it can be saved by replacing what beeing damaged, but without a poper cleaning your phone will give in. In a few weeks or at most a few months (depends how wet your board got)At this point parts of the logic board are corroded and the water has eaten solderconnection that seldom can be replaced (meaning your phone has no value anymore)

Since you have an iphone 6 (nice phone) i would go with option 1)

IF You want to deal with it yourself:

You can use a soldering iron to remove the emi shields, do that and soak the board in a container with 99% isopropyl alcohol and cleaning it gently and very very very VERY thoroughly.

Now replace those burned/shorted components (you cant do it without hot tweezers or a reworkstation)

another quick clean

and let it dry for 2 days

give it a try.

To be clear, chances are if you not a experienced micro solderer, you might do more harm than good. I do not want to discourage you but this is a matter of equitment :-)

hope it helped somewhat.

Good luck Sir