Identify Red Algae?

[jonto]

Hello AGAIN folks. One corner of my tank has this reddish looking algae growing. Its been there a month but was just a small spot. Now it seems to be starting to spread. Can you guys tell what it might. There is also brown diatom outbreak going on throughout the tank. and the water is clear.
Going to do full water tests this afternoon and post the results.
Could it be the red slime algae?

75gal tank on started 8/11/17
BRS Pukani(70 lbs)
Caribsea Aragonite sand
Red Sea Coral Pro Salt
Octo1000 HOB skimmer
Aquaflow 110 with Chemi-pure Blueand Poly filter
2 Starfire led lights (with 3 channels)
RODI water

384587

[thegrun]

cyanobacteria

[jonto]

Ok, all the tests I have results after 20% water change 4 days ago:

pH… (Diliss Digital) ……... 8.4
kH … (Hanna) ……….…….. 6.9
Amonia … (Red Sea) …….. 0
Nitrite … (Red Sea) ………. 0
Nitrate… (Red Sea) ………. 0
Salinity … (Milwalkee) ….. 1.024
Phosphate … (Hanna) …. 0
Calcium …. (Salifert) ……. 330
Magnesium (Salifert) …. 1320
Temp …………..…………….. 79.5

Seems the Caicium and kH are low but would these lead to my problems? Beginning to wonder if a salt brand change is in order.
I'm beginning to get so discouraged as it seems I'm doing things right but still have problems.
I did notice tonight when doing the pH test that the yellow probe was showing a lot of tiny specs of black particles floating by. Also notice there seems to be a lot of scum floating on the surface. Would a power filter help get rid of the gunk?
I'm at a loss. What do I need to do?

[jonto]

My local PetSmart carries the Marineland Magnum 360 and the Fluval 406 canister filters. Would one of these be good for periodically removing the surface scum and the fine black particles I have floating in my tank if I hold the intake close to the surface?
I'm just reaching out for ideas here! LOL

[Daddi0]

Do you have any corals? Personally I think the 8.4 PH combined with the low alk/cal could use a little correction. Dont get discouraged!! it could be way worse.

[Daddi0]

My local PetSmart carries the Marineland Magnum 360 and the Fluval 406 canister filters. Would one of these be good for periodically removing the surface scum and the fine black particles I have floating in my tank if I hold the intake close to the surface?
I'm just reaching out for ideas here! LOL
I sometimes point my pumps towards the surface a bit to get good movement on the surface. I dont think you would be able to just skim the top with a fluval. Perhaps a fine mesh net? Maybe try to siphon a bit off the top when you do a water change?
Cheers! Mark

[jonto]

I have 1 small Solomon, Zoanthus spp that was a freebie. It is open and doing fine.

[jonto]

I have good water movement on the surface.

[Daddi0]

Any idea what the black specks are? Carbon?

[jonto]

I'm thinking it might be carbon. I totally rinsed the 2 bags of Chemipure Blue before putting in the Aquaflow 110 though.

[Daddi0]

Out of curiosity how much flow do you have?

[jonto]

I have 2 Jebao PP8's. Both set to low but my 2 anemones have a lot of movement.