Bugs ate my Zoas

[ZoaSue]

Hello, new to saltwater after 20 years away. I have more patience now, and want to do things correctly. I had a small zoa fragment that was beautiful. The rock was completely covered. Then, one day when I forgot to turn on the light, I saw bugs on the closed-up zoas. After some research, I did a freshwater dip. The zoas came back, were still beautiful. The bugs increased, did another dip. The zoa started to die. I now have a nearly-bare rock with some blue patches where polyps were, and one brownish polyp on one side. Have no idea if I should give up, or if it can come back. I am incredibly sad- I had a zoa 20 years ago that never opened, and died.
Still have these bugs. They are tiny, do not look like nudibranches based on image research and viewing under a magnifying glass. They look like little shrimp-bugs. The polyps they were on were closed, did not open. They do not like the lights.
I followed the instructions I found for the freshwater dip, and then for melafix. The zoa started to disappear shortly after- like ice melting. Researching dips, I found CoralRevive, which doesn't treat pests(?) as I understand it. I also found instructions for a dip with Beyer, but the bottle recommended is for mites and things outside. I am not comfortable using it on a living animal.
Is it reasonable to combat the bugs in the future with a fish like the pink streak wrasse, rather than with dips? I'd rather find a natural predator. It's a 20 gallon peninsula-style nano tank. It already has: 1 damsel (yellow), a cleaner shrimp, an anemone, three snails, a stomatella snail, a feather duster and five or so hermit crabs. The zoa is on the highest rock. Ph is 8.2, ammonia is low, nitrates are low, nitrites are low. I turned the heater down, the temp is 72 degrees currently. What can I adjust for the zoa or for future coral? What fish or animal can I get to eat the bugs?
Thank you in advance for your help.

 

[ZoaSue]

Did it look like either of these

They appear to be amphipods.

 

[Cthulukelele]

They appear to be amphipods.

Do you have any photos of the zoas/tank? Like we were discussing, amphipods have been reported to occasionally chew on zoas (particularly their skirts) if they're in large quantities, but there are a lot of other things that could be causing them not to do well unless you're seeing them actively feeding on the live zoa flesh (not the detritus around the flesh the flesh itself they're naturally detritivores) in which case getting something like a pink streak wrasse would help, but most fish will eat amphipods greedily not just pest eating fish.

 

[AquaLogic]

It's going to take some photos in order for anyone to help. It's hard to help by description alone. I'm not sure the Zoa's would waste away even if they were being eaten, but I'm not a Zoa expert. It could be that something else was killing them and the bugs are scavenging, but I'm not saying it isn't possible it's just the bugs.

 

[VintageReefer]

They appear to be amphipods.

There are many species of these and some are suspected to eat zoanthids.

Unfortunately they do not just live on the zoa rock. They can be anywhere in the tank or other rocks. Coral rx and revive both will kill them. But it’s not realistic to expect to get all of them because you would need every rock dipped

What eats them? Yes various wrasse will eat them, along with a mandarin. Wrasse can be semi aggressive though.

A mandarin is a beautiful and peaceful fish that will hunt and eat them all day. If you run out of pods you can buy them (the safe ones) or you could return it to the fish store. Some mandarin can also be trained to eat mysis

 

[VintageReefer]

And, I don’t mean to dismiss anyone else in this thread! It’s possible you have another issue and the pods are eating decaying portions of zoanthids.

Picture of the zoas and tank under white light is needed along with full parameters, actual numbers, and your lighting fixture brand model and it’s settings

 

[Reefing_addiction]

There are many species of these and some are suspected to eat zoanthids.

Unfortunately they do not just live on the zoa rock. They can be anywhere in the tank or other rocks. Coral rx and revive both will kill them. But it’s not realistic to expect to get all of them because you would need every rock dipped

What eats them? Yes various wrasse will eat them, along with a mandarin. Wrasse can be semi aggressive though.

A mandarin is a beautiful and peaceful fish that will hunt and eat them all day. If you run out of pods you can buy them (the safe ones) or you could return it to the fish store. Some mandarin can also be trained to eat mysis

I love my mandarin. 90% sure she only eats copepods , maybe smaller amphiopds? Males are larger so they may be able to eat the bigger ones

She eats frozen too when she is feeling adventurous

 

[VintageReefer]

They should eat both, along with live baby mysis/brine, water fleas, and other tiny bug like creatures

The Ultimate Guide to Mandarin Goby Diet: Unveiling the Secrets of Feeding these Colorful Reef Fish - Mandarin-Palace.com (UPDATE )

Mandarin Goby Diet: Discover the essential food requirements and feeding habits of Mandarin Gobies to ensure their optimal growth and health.

mandarin-palace.com

 

[Reefing_addiction]

They should eat both, along with live baby mysis/brine, water fleas, and other tiny bug like creatures

The Ultimate Guide to Mandarin Goby Diet: Unveiling the Secrets of Feeding these Colorful Reef Fish - Mandarin-Palace.com (UPDATE )

Mandarin Goby Diet: Discover the essential food requirements and feeding habits of Mandarin Gobies to ensure their optimal growth and health.

mandarin-palace.com

At least I know who keeps the water fleas in check….

 

[ZoaSue]

It took some doing, but here are pictures. I circled the amphipod/bugs and the remaining zoas. They are too big/solid to be copepods, based on what I have seen at the fish store and online. They are not frilly like nudibranches. They appear to narrow at the end, which would rule out isopods.
The zoas were beautiful for months and months before suddenly withering when the bugs showed up. The bugs actively crawl/walk on the polyps.
Research I have already done: what kind of pods these might be - amphipods, most likely. I read on Reef2Reef posts that lower temperatures can help, hence the reduction to 72 degrees. I know zoas prefer higher temps, though. I had a bubble stone going when I was doing the melafix dips to help the zoa recover. The damsel fish loved it, the cleaner shrimp hated it. It is off, now, as the zoas were not opening either way.
Tank info: It's a Fluval light (Fluval Sea Marine 3.0 LED Aquarium Lighting for Coral Growth, 22 Watts, 15-24 Inches). I wish I could tell you more about the tank. I bought it 8 years ago. It ran with just live rock and live sand for 8 years, and then I finally had time to put fish/coral in the tank. (CPA- just left public accounting) I had to clean up an algae bloom - green hair algae- on the glass (not on the rocks, surprisingly) before adding anything. There is no algae problem currently, has not been since the introduction of animals.

 

[ZoaSue]

There are many species of these and some are suspected to eat zoanthids.

Unfortunately they do not just live on the zoa rock. They can be anywhere in the tank or other rocks. Coral rx and revive both will kill them. But it’s not realistic to expect to get all of them because you would need every rock dipped

What eats them? Yes various wrasse will eat them, along with a mandarin. Wrasse can be semi aggressive though.

A mandarin is a beautiful and peaceful fish that will hunt and eat them all day. If you run out of pods you can buy them (the safe ones) or you could return it to the fish store. Some mandarin can also be trained to eat mysis

Mandarins are very pretty, but I think my tank may be too small. I would love to have one, though.