One Species has low PE

[MHG]

So I have a sps dominant 60g cube. its about 4 years old. I did have a 90% crash about a year ago for reasons unknown. All I can say is when I started vacuuming the shallow sand bed during weekly water changes. things turned around.


So things are bouncing back nicely. I have a colony of Copps Turquoise Hoek that's about as big as a soccer ball. a bunch of other sps smaller colonies that are growing well. and a zoa garden along the front. Two colonies both the same species have little to no PE. Forest Fire Digi. It looks white with orange dots. Its been doing this over the past few days. They are in different parts of the tank and nothing at all in the tank has changes as far as lighting and flow.


My alk is at 8
Calc is at 400. Had a bit of a growth spurt so I am catching up to the normal 450 I keep it at.
Nitrates are just detectable at .02.

PO4 is zero, PH is around 7.9-8.2.


The only thing I did recently was change my batches of BRS alk and calc the week before.

Just looking for a few suggestions...

 

[Pife]

Are they the only montiporas in your tank?

 

[MHG]

Yes, both from the same mother colony.

 

[ajcanale]

Mg level?

 

[MHG]

1440. Never changes...

 

[markalot]

Do you see any small black dots on it or any skin loss?

I really don't know, too inexperienced, but 2 weeks ago I did something that discolored my red cap monti, purple cap, and mystic sunset and they are just now recovering. No acro suffered, no other corals suffered, I'm still at a loss. I thought sure I was crashing my tank when it happened.

 

[Pife]

I don't know if montipora nudibranches attack them but I think they might. Hopefully someone can chime in with more experience.

 

[Bootlegger]

I had and still having to some degree poor PE, especially with my digitata and caps. I made some changes in lighting and my SPS have bounded back nearly 100%. The Montis are all showing less PE than what my tank typically has. One day they had it and one day it's gone.

I'm now running GFO and Carbon trying to see if it is an impurity issue. Thus far no improvement. I have also balanced my hardness to calcium ratio...and no change. Everything is perfect on paper but PE is not good.

If I had to make a guess, for me, it's probably by fish as I have a nipping Purple Fiji Puffer and a Flame Angel who likes to graze. My point here is consider one of your fish may be doing a drive-bye and agitating some of your coral.

 

[MHG]

No changes in the tank since I re-aquascaped after the crash. Sabe food, feeding, lighting, water changes. No new additions... Never had bugs or any signs of bugs. Added some amino acids and it is helping abit. But that's like giving someone an adrenalin shot. sooner or later it will wear off.

 

[markalot]

Any temperature changes outside your tanks normal range?

 

[MHG]

No. Chiller keeps it within 2 degrees. Salinity spot on..strange how two different colonies from the same parent colony...