Strange White Lattice/Stringy Growth on Zoas

[Killgannon]

Can’t anyone identify this? It’s not like a typical sponge I’ve encountered. Sorry for the pic, but it’s only visible at night when the zoas are closed. It doesn’t blow off, but I can pull it off easily the tweezers but seems to retract a bit (not sure about this) when I start messing with it. It’s got little fingers spines coming off and is almost like a lattice work

Params:
Temperature: 77°F
Salinity: 1.025
pH: 8.2
Alkalinity: 9 dKH
Calcium: 410
Magnesium: 1320 ppm
Nitrate: 2.5 ppm
Phosphate: 0.02 ppm
Ammonia: 0 ppm

 

[Dragen Fiend]

If I had to guess based off the picture. I'd go with some sort of sponge.

 

[ISpeakForTheSeas]

Can’t anyone identify this? It’s not like a typical sponge I’ve encountered. Sorry for the pic, but it’s only visible at night when the zoas are closed. It doesn’t blow off, but I can pull it off easily the tweezers but seems to retract a bit (not sure about this) when I start messing with it. It’s got little fingers spines coming off and is almost like a lattice work

Params:
Temperature: 77°F
Salinity: 1.025
pH: 8.2
Alkalinity: 9 dKH
Calcium: 410
Magnesium: 1320 ppm
Nitrate: 2.5 ppm
Phosphate: 0.02 ppm
Ammonia: 0 ppm

It does seem to be a sponge; it's most likely harmless if the zoas are open during the day:

Yeah, that's definitely a sponge. Most sponges are completely harmless/beneficial, but some can be invasive and/or harmful to corals (thankfully, these are rare).

To tell if a sponge is chemically harmful: if a healthy, established coral starts closing up or looking to be in bad shape on the side closest to the sponge as the sponge grows closer to it, and nothing else has happened (lighting changes, parameter swings, pests, etc.) that could explain it, then the sponge is probably chemically harmful.

Chemically harmful sponges are very rare.

For invasive sponges: unless it shows signs of being chemically harmful or starts actively growing over and smothering a coral's flesh/polyps, it's harmless. These can grow over the skeletons of corals, around the base/stalks of corals, even up into the water column above corals (where they're over the coral but not growing on the flesh or polyps themselves), etc. without harming the coral at all - as long as the coral flesh and polyps can get food, light, and flow, the sponge is harmless.

Invasive sponges are moderately rare.

Invasive and chemically harmful sponges are incredibly rare.