Problems with wild A. cacatuoides. Ph to low?

[Robert Marshall <w22ram@morgan.ucs.mun.ca>]

Purchased 5 unknown Apisto. fishes.  4 are cacatuoides (other maybe a
female Agassizii but they are not collected in the same area from
readings) and I have had one die and one in the process.  Not eating
much which include flakes, pellets, freezed dired blood worms and brine
shrimp and live grindel worms.  The ph is 6.3 and 9 dc of total
hardness.  Thinking that the ph is to low.  Any suggestions?

Tank 50 gal have 3 Angels, 16 neons, 7 red eye tetras
Tank is 2/3 planted and there are 3 coconut shells for them to hide.

Could it be that there wild and are not adjusted? Not really fearful and
are seeming to be going through the breeding behaviour.

How could I raise the ph?  I hear baking power.  Tap water is naturally
low and want to raise it to about 6.6.  Any suggestion will be helpful.
Thanks.

p.s. Yes I finally got Apisto fish