Pink Coralline Dieing (water chemistry question)

slice · Feb 17, 2011

I think this is a water chemistry issue...

I noticed last night that my pink coralline is turning white in most areas. The purple coralline has not changed color, the green seems the same, the red is continuing it's steady encroachment. Only the pink looks different.

All livestock seem normal, fish doing their usual thing, leather has all polyps out, zoas shine, 'shrooms in full "bloom". I tested the usual suspects just to rule them out:

Ammo, trites and trates are undetectable, pH 8.4, temp 79*.

The only thing that is different lately is that I have not done a w/c in about 2 weeks and I've allowed purple coralline to cover most of the back glass. Plus I now have a few corals in the tank. I took to heart an article posted the other week in another forum about w/c's alone not being able to keep up with calc and mag levels. That article suggests that my tank's water has seen a slow, steady decline of these attributes.

I conclude that this issue is most likely a reduced level of essential water chemistry for good coralline health.
My need for cal/alk and mag tests just jumped way up on my priority list. The need to monitor and adjust these levels in advance of getting more finicky critters is also bumped up on the list.

Do you believe my reasoning is on point, or am I off base?

dougers31 · Feb 17, 2011

It is most likely water chem IMO(could be lighting). But I wouldn't worry about it as long as you have the purple growing well.

jledon4 · Feb 17, 2011

this tends to happen when you change the lights. IMO if you haven't changed lights, the cause should be water chemistry (get the test quick, your alk could be on the 7's dkh. coralline is one of the things in our tanks that consumes the most alkalinity of all. by having your back wall fully covered with it, all you are doing is making your life harder due to the need to be dosing more to keep up with it.

slice · Feb 17, 2011

jledon4 said:
this tends to happen when you change the lights. IMO if you haven't changed lights, the cause should be water chemistry (get the test quick, your alk could be on the 7's dkh. coralline is one of the things in our tanks that consumes the most alkalinity of all. by having your back wall fully covered with it, all you are doing is making your life harder due to the need to be dosing more to keep up with it.

Yep, I was thinking that the coralline on the glass might be out competing with what is on the rock.
I will have a clean back glass by the end of the weekend....and get the test kits

Thanks for both of your replies!

re-fin-away · Feb 17, 2011

I have never thought about the competition with corals. Good point. I think I might get out the scrapper and go to work on the back wall of my tank. Would you do it in stages or scrape it all at once?