Why are my Zoas always closed?

[KantGetRite]

Good Morning! First I'll give you my system as it is setup now and my readings for all the normal stuff and you can advise me from there.

I have a 20g Long setup with a 10g Sump/Refugium.
I have 165W 55 LED Full spectrum light that hang 14 inches from top of water.
I have 200 gph return pump and 2 koralia nano 425 and HOB overflow

Stocking:
1 Royal Gramma Basslet
1 Purple Firefish
1 Six Wrasse
3-5 Hermit Crabs
Various Snails
2 Heads of Frogspawn
1 Head of Gold Hammer Coral
2 Heads of Green Hammer Coral
2 Heads of Candy Cane Coral
2 Ricordea Mushrooms (Small)
1 Green Hairy Mushroom (Small)
Tubbs Blue Zoa (about 15 polyps)
Radioactive Dragon's Eye (about 5 polyps)
Fire and Ice Zoas (about 5 polyps)

My readings are as follows:

Ammonia: 0ppm
Nitrite: 0ppm
Nitrate: Less then 5ppm
pH: 8.0
Salinity: 1.025
Temp 77.9
Calcium: 420
Alkalinity: 4.0 meg/L
Magnesium: 1280

All of my other corals seem to open and even seem to be growing (the tentacles on the frogspawn, whisker, and hammer coral bubble up from time to time though) and doing well. I have tried moving them around in the tank for lighting and flow. Any ideas why they aren't growing and opening up? Also, I heard that the do better in "dirty" water and I keep having some algae blooms so I don't think that my water is exceptionally clean either.

 

[TheTodd]

Do they never open or just not much? I know my Blue Tubs spend a lot of time closed, but all of my others are open most of the time. Many have been in a tank with no skimmer and just relying on water changes to keep everything in check. I'm in the process of transferring them into my. 60g cube, which has a skimmer, so hopefully they continue to do well.

 

[KantGetRite]

After the first day I have seen my fire and ice or dragon eye open. Tubbs opens sometimes but it's been like 5 weeks since the last time

 

[bribo12]

My tubs are always open, that's weird. Have you checked for any type of pests that could be irritating them? How intense are your lights set at?

 

[54seaweed]

try cutting your whites back to about 1/2 a day or 2 most zoa's don't like intense lighting see if that makes a difference

 

[Phranque]

try cutting your whites back to about 1/2 a day or 2 most zoa's don't like intense lighting see if that makes a difference

That, and if they're not dimmable, try moving the lights a little higher. A 20 long is a fairly shallow tank for 165W of LED's.... or try sliding the zoas under a rock shelf so they're not in direct light (or both). My first thought in this situation is they're retracting from the intensity.

 

[Rmckoy]

I had the same issue with zoas when I first started.
I am using T5HO 6 bulb fixture
3 10000k and 3 blue
as the bulbs were old and due to be changed I experienced zoas staying closed
anything I read about them states they require strong lighting and after changing the old bulbs to new they are open everyday, growing and reproducing throughout the tank
I don't have any experience with leds and not sure but a good rule is to place at the bottom and slowly move higher ,
I use this for placing all corals

 

[Redwolf91]

Forgive my answering a question with a question, but my brain isn't processing right now... Isn't the alkalinity very low and could it be the cause?

Sent from my Z750C using Aquarium Advice mobile app

 

[KantGetRite]

Alkalinity is in the acceptable range.

 

[J8kpin]

I have marine land LEDs , and my zoanthids opened after being in the tank for 2 hours. They look to be more open in moonlights, but not as much in daylight. Mine are towards the bottom, and they seem happy.

 

[Ingy]

Hey red.

Conversion factor is 2.8 dKH per Meq/l.

So he is at 11.2 dKH. Perfect.

 

[Redwolf91]

That is the part my brain was not processing lol, thank you

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