Thanks for the help, can I ask for a little more?

I would like to start off by saying thank you for all the help in the past. Yes this is my first post but I have been reading the forums for a long time and have learned just about everything I know about reef tanks from these forums. I obviously have a lot to learn. I will try to get to the point and let you know my issues and what I think is relevant information.



I am having 2 issues for what I know might be the same issue.



1. very light brown fuzz all over base rock-smells really bad

2. low PH 7.95 highest I can get



I want to add more coral but seems that the fuzzy stuff is aggravating the corals keeping them closed. The zoas keep forming new polups under the frag away from fuzz while the ones on the top melt away and die.



tank has been setup about 6 months



90 Gallon tank 30 gallon sump

80 lb base rock 20 lb argonite sand in DT

5 lb of live rock from lfs for coraline seed

refugium with 5lb argonite sand and rubble

reef octopus 150nw skimmer

GFO reactor

CO2 scrubber on skimmer



Coral:

only 3 coral GSP, hammer, bam bam zoas



Fish:

3 small spotted cardinals

4 blue chromis

1 neon dotty back

1 canary angelfish

2 clownfish

1 banded coral shrimp

1 emerald crab

7 hermits scarlet and blue legs



Water params

Temp 80F

PH 7.91 at end of lighting cycle

ALK 10.3

Phospate 0.009198 =(3*3.066)/1000 Hana ultra low phosphorus checker

CA 430

MG 1350

Nitrate .05



Kalk and 2 part, believe it is the coraline eating most of it



How do I slow down algae growth, and any other Ideas for low PH



Thanks for any suggestions.