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?

 

[bsn_rn_cen]

I have black sand in 2 tanks. Set up and size is identical. Sand was even from the same bag. One tank has coralline everywhere. One has none. I've never figured it out..

 

[X-37B]

Probably a hex/curse lol.
Coralline takes a while and likes stability.
You need to test to determime alk and ca useage.
Doing a water change every 3 to 4 weeks is not stability imo.
I did 3 gallons a week in my 25 nano and still had to dose 2 part as an example.

 

[chaostactics]

Probably a hex/curse lol.
Coralline takes a while and likes stability.
You need to test to determime alk and ca useage.
Doing a water change every 3 to 4 weeks is not stability imo.
I did 3 gallons a week in my 25 nano and still had to dose 2 part as an example.

Did you have organisms that utilized those elements though? I mean of course, any reef tank will have some utilization of those elements but I lack SPS, LPS, or even a considerable invert population. After getting consistent and stable results for many weeks I stopped testing. As I lack organisms that will heavily utilize Ca/Alk/Mag and am using reef crystals on a consistent water change schedule testing becomes a pretty moot point.

 

[chaostactics]

I have black sand in 2 tanks. Set up and size is identical. Sand was even from the same bag. One tank has coralline everywhere. One has none. I've never figured it out..

I had a tank 3 tanks ago with black sand that had pretty decent growth too and I was using plain instant ocean and no reef crystals and actually had Stoney corals... go figure.

Btw nice credentials set. I found the CEN to be waaay the heck harder than the NCLEX.

 

[Ef4life]

I don’t have an issue with coralline growth in my Biocube with black sand. Growth just takes time.

 

[chaostactics]

I don’t have an issue with coralline growth in my Biocube with black sand. Growth just takes time.

So normally I'd think that but I've had younger tanks in the past at least start showing growth and friend up the street whos tank is only just getting to two months an has pretty explosive coralline growth. Super newbie whos still learning husbandry.

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

 

[X-37B]

Try running a magnet through the sand.
I have heard some black sands are magnetic and have issues. Dont remember what issues people had
Just a thought. Maybe one bag is and one is not magnetic.

 

[bsn_rn_cen]

I had a tank 3 tanks ago with black sand that had pretty decent growth too and I was using plain instant ocean and no reef crystals and actually had Stoney corals... go figure.

Btw nice credentials set. I found the CEN to be waaay the heck harder than the NCLEX.

Oh I agree, one of my first questions had a chemo drug I had never heard of in the scenario. I remember thinking "oh this is going to be bad." LOL.

I did change the sand in the tank that never grew coralline when I had a hydroid breakout. It still doesn't have any but it was a pretty recent change.

 

[TriggerFinger]

I get the best coraline growth in my 29g barebottom with liverock from the ocean. It’s an observation tank for newcomers so I won’t ever put this rock in my DT. I have to scrape the glass to see inside because it grows so thick. My 90g has old rock that came with the set up and one piece of the ocean rock along with new special grade sand. Both tanks have been running for over 1 year and I’m just now starting to get coraline on the gyre in the 90g. I make rodi at home and use Fritz for both tanks. The coraline infested tank has a reefbrite strip and the 90 has viparspectras...wonder if lighting plays any part??