Acro Receding Bottom Up?

heifinator · Nov 24, 2021

I've recently been having issues with acro frags in one of my systems dying from the base up.

Been trying to find a root cause for a few months now but clearly I am missing something as none of the adjustments I've made have seemed to resolve the issue. Over the course of about 3 weeks any acro frag that I put in this system will recede from the base up and eventually die. Luckily I have another system without this issue so I can move things back there to heal...

Parameters:

Temp 78
Alk 7.5
Calc 420
Mag 1200
Nitrate 20
Phos 0.01 (Hanna UL Phosphorus)

Par for the frag rack that I've been putting acros on is around ~225-275 as measured/corrected with an MQ-200. Any help is greatly appreciated!

Day 1 ^^^

Day 14 ^^^

ScottB · Nov 24, 2021

Lets compare the two systems.

Age?
Live rock?
Fish?
Nutrients?

heifinator · Nov 24, 2021

Both systems are 3+ years old. Both started with dry rock, seeded with 10% live rock from LFS.

This system only has 5 fish in it (its a reefer 250). Kole tang, two clowns, royal grama, and a mandarin dragonet.

Nutrients was my first thought (PO4 is pretty low) so I dosed PO4 daily for a month but no improvement was noted.

I checked for stray voltage & sent in an ICP test which didn't show any major gotchas.

Charlie’s Frags · Nov 24, 2021

What are you dosing?

ScottB · Nov 24, 2021

heifinator said:
Both systems are 3+ years old. Both started with dry rock, seeded with 10% live rock from LFS.

This system only has 5 fish in it (its a reefer 250). Kole tang, two clowns, royal grama, and a mandarin dragonet.

Nutrients was my first thought (PO4 is pretty low) so I dosed PO4 daily for a month but no improvement was noted.

I checked for stray voltage & sent in an ICP test which didn't show any major gotchas.

More fish/more feedings is always a basic tactic I prefer.

So these pieces recover when moved to the other system?

jda · Nov 24, 2021

That looks OK for a move two weeks ago. Some frags just die back a bit. Just stick to the basics and don't chase anything while monitoring for other changes. If you are feeding your fish 3-4 times a day and they are happy and growing, then there is enough N and P for the coral to get through the fish waste - I would not dose any P at all... probably all that you dosed got bound up almost instant by the aragonite and would not have helped the coral much anyway.