Acan and chalice is dying (receding)

[Fishingandreefing]

Tank is almost one year old and had the acans for about 6 months. They were doing great but lately it’s receding to including a chalice.

Other corals are doing ok so far.

alk around 7
Nitrate 2-5ppm (Salifer)
Phosphate .02 (Hanna)
salinity 1.025
Temp around 78

No clue why all the sudden started receding

I have a crab that hosts on a rock of ricordeas and hardly leave it. And never seen it close to the acans.

there’s a favia coral next to the acan but I don’t think it’s stinging it as the receding on the acans are all the way around on the bottom.

 

[vetteguy53081]

Some possibilities are:
Ammonia or nitrate spike
False nitrate readings
Lighting
Too much water flow
Pests (little bugs)
Mag may be low

your alk is low

alk 8-10
Mag 1300
Ca 440
Nitrate < .4
Phosphate < .04
Moderate light and water flow

 

[DaneGer21]

When my nitrates creep up I notice all my chalice get puffy and weird.

You would think my few sps would be the first to show but they’re not, it’s my chalices.

Also mentioned above, alk is a little low

 

[Fishingandreefing]

Just an update. I acquired another mini acan colony. It was doing great for a few months but then suddenly went down hill. It’s a sps dominated matured tank. It’s sitting on the bottom getting about 80 par and low flow.

I do feed the tank with reef energy.

alk usually drop to 6-7 (my sps are sucking up all the alk and cal I think. Dosing kalk with ato and adjust it with 2 parts)

nitrate .11
Phosphate .10
mag 1350 (bumping to 1400-1430)
Cal should be around 450
salintiy 10.25/26

most of lps are doing ok and sps are growing.

I am running a bit of rox .08 carbon and gfo (about 35% recommended dose)

any help be greatly appreciated.