Help Please: Does black sand inhibit coralline growth?

[chaostactics]

So in my last tank I had zero coralline growth except on the glass below the level of the sand bed. Myself nor anyone on the forums could figure out a good explanation for that. 

I moved, set up a whole new tank, and used fresh bags of Hawaiian Black Arag-Alive! Live Reef Sand. 4 months in no coralline algae growth to speak of. I've treid two bottles of Helix (figured it was snake oil anyway), I have no hard corals whatsoever that could be taking up Ca and large quantities of trace elements.

 

The tank gets a 20% water change with Reef Crystals every 3-4 weeks (I don't bother to test after the tank stabilized) so Ca, Mag, Alk, and trace elements shouldn't be an issue. The tank pH fluctuates between 8.1-8.3 pH night and day. 80 gallon tank with 80 ish lbs of Carbisea life rock* and a few lbs of actual live rock to seed the tank. 

 

Any ideas. Could it be the black sand, or a hex/curse?

 

 

*yes with Life rock it would be difficult to see coralline growth. but even on barren rocks/shells/segments of live rock I break up for mounting frags glass of the tank back wall of the tank etc. no growth at all?
 

[DreC80]

I don't think sand has anything to do with it.  I think it's just a tank maturity issue.  Sometimes coralline can take quite a while to show up.  Why not try seeding it with a few pieces of rubble rock (that has coralline) from someone else's tank?

[SliceGolfer]

42 minutes ago, chaostactics said:

The tank gets a 20% water change with Reef Crystals every 3-4 weeks (I don't bother to test after the tank stabilized) so Ca, Mag, Alk, and trace elements shouldn't be an issue. The tank pH fluctuates between 8.1-8.3 pH night and day. 80 gallon tank with 80 ish lbs of Carbisea life rock* and a few lbs of actual live rock to seed the tank.

Do you know what your alk/ca/mg levels are? What is your light source? Have you placed any rock, plug, or shell in the tank that has coralline growing on it..

[chaostactics]

3 hours ago, DreC80 said:

I don't think sand has anything to do with it.  I think it's just a tank maturity issue.  Sometimes coralline can take quite a while to show up.  Why not try seeding it with a few pieces of rubble rock (that has coralline) from someone else's tank?

Yes I have about 3-4 lbs of live rock and rock rubble tucked in my rock work all over as well as some in the sump. 

[chaostactics]

3 hours ago, SliceGolfer said:

Do you know what your alk/ca/mg levels are? What is your light source? Have you placed any rock, plug, or shell in the tank that has coralline growing on it..

I haven't tested my Ca/Alk/Mag levels in a little while. After the tank had 4-5 tests all in the same stable and acceptable range. I've just kept up my water change/skimmer/filter sock routine. Since I don't really have any organisms that would rapidly deplete those elements and I'm using reef crystals its essentially a moot point.  

Light source is a Radion XR30 pro. I have around 3-4 lbs of LR and rubble that is heavily encrusted spread throughout my rock work. 

[chaostactics]

Tank is nearly 6 months old now that I look back at my Apex logs. 

[DreC80]

6 hours ago, chaostactics said:

Yes I have about 3-4 lbs of live rock and rock rubble tucked in my rock work all over as well as some in the sump. 

Sounds like you are on track.  I think it took my tank like 8 or 9 months before I saw coralline growth.  I've heard some people say it takes a little longer with leds.  Not sure if this is true though.  I think it's just a matter of time for nature to do its thing.