What’s caused my Rastas to shrink?

[Ober_Reef]

Hello All,

Just wondering what may be causing my rastas to shrivel up like this. They were doing very well and adding a head every week or two, all of my other coral seem to be doing well. I just moved it to this rack today, previously I had them on my sand bed.

 

[Saltyreef]

What are your params?
They look open...

 

[Ober_Reef]

What are your params?
They look open...

Here they are everything has been good, I have been trying to increase nitrates and phosphates to battle Dinos and the rastas haven’t changed since the increase. Previously they were showing more stalk and not a shriveled.

 

[tippin.turtle]

Here they are everything has been good, I have been trying to increase nitrates and phosphates to battle Dinos and the rastas haven’t changed since the increase. Previously they were showing more stalk and not a shriveled.

Do you monitor your Ph? How long have you had those rastas? They look open to me as well.

 

[Ober_Reef]

Do you monitor your Ph? How long have you had those rastas? They look open to me as well.

I do, a few days ago I was low around 7.8. They are my oldest around four months old.

 

[tippin.turtle]

I do, a few days ago I was low around 7.8. They are my oldest around four months old.

I run a CO2 scrubber as I'm in a basement with decreased oxygen availability. Your Ph will be at its lowest early in the mornings when lights are off. This would be a good time to assess your Ph levels to ensure they are not falling bellow 7.8. Also, zoanthids can be "finiky" at times so if all your other corals appear normal then I would wait and see if they do not go back to "normal" as well.

 

[BroccoliFarmer]

Water’s cold? Makes me shrink

 

[vetteguy53081]

Important to know the water quality provided in safe range AKA parameters. Test kits are a must to monitor tank. . .. Fish dont talk - Test kits DO and stay away from API kits. There are a number of factors why zoas close up. Some are water movement/flow as zoas do not require the consistent high flow conditions that SPS corals do. I would consider a moderate flow environment ideal but Zoanthids, like most corals, can adapt to low or high flow. In high flow, you will typically see polyps grow closer to the rock with shorter stalks. Another is lack of feeding and food as infrequent feeding and ultra low nutrient conditions can lead to entire colony meltdowns. Target feeding is not a requirement as Zoanthids are photosynthetic. I have found that target feeding Zoanthids always provides mixed results, when a food particle falls onto the polyps.

Back to parameters, good water quality is a must.
dKH: 8.0 - 10.0
Calcium: 420 - 440
Magnesium: 1300 - 1350
Iodine: Maintained via regular water changes or manually at small dosages
Temperature: 78-79 degrees
pH: 8.1-8.3
Phosphates: .02 - .03
Nitrates < 5

Asterina stars, little tiny tiny spiders and nudibranchs also will make them miserable to point of death as will aptasia, worms like spinoids or vermetid snails. A few things to look for. Hope this helps

 

[tippin.turtle]

Vetteguy is right.
Parameters are the first place to start when trying to diagnose any issue.
This is a handy chart for reference I keep on my computer desktop.

http://reefkeeping.com/issues/2004-05/rhf/

 

[Ober_Reef]

My ICP test did show I was lacking in iodine so I have been dosing the recommended dose via triton. As for my test kits I bought the recommended test kits from BRS, I’m mostly Hanna now as I use Hanna testers for PH, dKH, Phosphate, and Nitrate. I have Hanna for Ca but don’t use it because it’s easier to use sealifert and a use aquaforest for Mg. Also every piece of coral I have bought I have dipped to reduce chances of pests. I will continue to look into ways to bring up my PH because this does seem like the most likely issue at the moment and I have my skimmer off while battling Dinos.

 

[Hooz]

Did you make any changes to your lighting or light schedule recently? I've found that lower PAR with longer photo periods seems to make bigger zoa polyps. Higher PAR, and higher flow to an extent, can make them shrink.

 

[Ober_Reef]

Did you make any changes to your lighting or light schedule recently? I've found that lower PAR with longer photo periods seems to make bigger zoa polyps. Higher PAR, and higher flow to an extent, can make them shrink.

This all happened after my moved them slightly a few months back(literally within a 2-3 inch radius from where they were before). I was thinking it may be too much light as well. Just strange the other ones seem to be fine.

 

[littlebigreef]

A modest water change is always a good 'pick me up' for zoas, I don't see you mentioning having done one recently in the tread. While it's good practice to dose lugol's (iodine) a small water change will also replenish iodine and all the other trace elements that get used up.

 

[Ober_Reef]

A modest water change is always a good 'pick me up' for zoas, I don't see you mentioning having done one recently in the tread. While it's good practice to dose lugol's (iodine) a small water change will also replenish iodine and all the other trace elements that get used up.

I normally do five gallons every Sunday but I am currently battling Dinos so I have not done a water change in almost two weeks. However these rastas have been this way for over a month. My ICP results showed I was lacking in iodine so I have been dosing iodine for about two weeks now as well.