Help! - Birdsnest and Poci STN from Base

Aclman88 · Jan 12, 2021

As stated in the title. I have two sps that have grown from frags. The birdsnest in particular grew rapidly in my tank for months. My Poci has started to STN from the base (second time it has happened, the first time it recovered completely) and I noticed it might be happening to my birdsnest.

I read that sometimes shading can result in the bases dying off, but not sure this is the case. Tank is a 20 tall lit with two ai primes. No major changes recently other than the addition of a nepthea and some shrooms.

Params:

Salinity - 35 ppt
pH - 7.8 - 9 (always stable in this range)
Alk - 8.7
Cal - 430
Mag - 1430
Phos 0.9
NO3 - ~5

I know phos is high, but it has been stable in this range for months now, and birdsnest was growing consistently in this range. All other corals are growing, puffy, and generally happy/healthy.

Thoughts on possible causes? I am wondering if there is not enough flow reaching that side of the tank.. I have two koralia 240s on either side pointing at one another. (I recently added the second, but this was happening before that addition)

PBar · Jan 12, 2021

Hello,
my first reaction would be probably shadow + low flow... but since the base of the corals are really white... how slow is the process? Days or weeks?

I’m not sure if it is a distortion of the picture but I’m already impressed by the fact that the poci was growing well in that part. Seems that not much light reach there (again, hard to say by only one picture)

Again, stn is always tricky... the problem is that, in my experience, shadowing tends to be very slow process... that’s why I’m not very confident with it.

Another possibility is bacterial infection (then dip would be an option)

Let‘s see if other suggestion pops up!

Aclman88 · Jan 12, 2021

PBar said:
Hello,
my first reaction would be probably shadow + low flow... but since the base of the corals are really white... how slow is the process? Days or weeks?

I’m not sure if it is a distortion of the picture but I’m already impressed by the fact that the poci was growing well in that part. Seems that not much light reach there (again, hard to say by only one picture)

Again, stn is always tricky... the problem is that, in my experience, shadowing tends to be very slow process... that’s why I’m not very confident with it.

Another possibility is bacterial infection (then dip would be an option)

Let‘s see if other suggestion pops up!

The poci was placed there a little while ago, but was still growing then (not really as fast though), but yes it is definitely in a darker area of the tank and there wasn't as much flow. About a month ago it had what seemed to be a polyp bailout, but it recovered quickly. The birdsnest I just noticed today, but it has been slow overall. The poci has been turning white over the course of over a week or so, but not sure if it is that the coral has been in a darker area for a while and it is just starting to show the affects.

PBar · Jan 12, 2021

This is really annoying... not easy to figure it out.

If we assume that there was no big shifts in the water parameters recently, I incline more to change the location of the poci and try to increase a bit the flow in the tank or at least near the base of the birdsnest...
In summary, I’m assuming that the birdsnest is stn in the base due to normal grow combined with a lower flow. And poci due to lack of sufficient light and flow.

The only thing that bothers me a bit is that fact that it is happening in both at the same time...

That would be my first course of action in my tank... still, I‘m curious for a second opinion...

vetteguy53081 · Jan 12, 2021

This appears to be shading
Other factors that cause this is:

change in lighting
Insufficient water flow
Alk spike
Low CA
mag high
Red or black bugs
High phosphate
High nitrate

min your case, mag is a little high- target is 1300

Aclman88 · Jan 13, 2021

Thanks. It seems to have stopped and not progressed, I’m hoping the extra power head will get rid of potential dead spots.

Aclman88 · Jan 13, 2021

vetteguy53081 said:
This appears to be shading
Other factors that cause this is:

change in lighting
Insufficient water flow
Alk spike
Low CA
mag high
Red or black bugs
High phosphate
High nitrate

min your case, mag is a little high- target is 1300

Thanks for the list, this will be good to keep on file. Could be the mag I’ll keep an eye on it.

Aclman88 · Jan 13, 2021

PBar said:
This is really annoying... not easy to figure it out.

If we assume that there was no big shifts in the water parameters recently, I incline more to change the location of the poci and try to increase a bit the flow in the tank or at least near the base of the birdsnest...
In summary, I’m assuming that the birdsnest is stn in the base due to normal grow combined with a lower flow. And poci due to lack of sufficient light and flow.

The only thing that bothers me a bit is that fact that it is happening in both at the same time...

That would be my first course of action in my tank... still, I‘m curious for a second opinion...

Thanks for this. I added a power head to the opposite side of the tank, but pointing at the colony and the polyps are getting some movement at the base that I don’t think was happening before.