Vermatid worms and coral growth issues

[hmc52]

Hey everyone. So I have had this tank for about 2 years. I once had a lot of corals and it was thriving but then I had a crash in my system. After giving it awhile to get everything right, I have been trying to add zoas into my system. I have just added some but they aren't opening. I checked all of my water parameters and everything is going well. I have the EVO 13.5 with everything stock except for a powerhead and a new light because the old one burned out. The new light is the Kessil a80. I am also having an issue with vermatid worms. Does anyone know if the will cause harm to the zoas?

 

[malacoda]

Immediate or direct harm, no.

When there is a lot of particulate in the water--zooplankton coral foods, detritus that gets stirred up, etc.--vermetids will put out long strings similar to a strand of spider web to catch the particulates and draw the strands back in to feed on what they caught. These strands can sometimes irritate nearby corals causing them to retract their polps, or in the case of zoas, cause the zoas to stay closed at times.

Over a prolonged time it could result in a coral slowly diminishing in health. But it will likely take quite a while giving you plenty of time to notice the irritation or closed behavior.

If you see any vermetids in or near your zoas you could just crush their tube at their base with a pair of needle nose pliers rather than waiting to see if they irritate the zoas.

If your zoas have been closed right from the moment you put them in the tank, I would suspect water quality, lighting, flow or some other major parameter rather than the vermetids.

You say you just added the zoas. When exactly--a few hours ago, a day, two or three days? Is it possible they just need a day or two to acclimate to your system? Or has it already been a few days?

 

[hmc52]

Immediate or direct harm, no.

When there is a lot of particulate in the water--zooplankton coral foods, detritus that gets stirred up, etc.--vermetids will put out long strings similar to a strand of spider web to catch the particulates and draw the strands back in to feed on what they caught. These strands can sometimes irritate nearby corals causing them to retract their polps, or in the case of zoas, cause the zoas to stay closed at times.

Over a prolonged time it could result in a coral slowly diminishing in health. But it will likely take quite a while giving you plenty of time to notice the irritation or closed behavior.

If you see any vermetids in or near your zoas you could just crush their tube at their base with a pair of needle nose pliers rather than waiting to see if they irritate the zoas.

If your zoas have been closed right from the moment you put them in the tank, I would suspect water quality, lighting, flow or some other major parameter rather than the vermetids.

You say you just added the zoas. When exactly--a few hours ago, a day, two or three days? Is it possible they just need a day or two to acclimate to your system? Or has it already been a few days?

Thank you so much for the response. So I have had them in there for a few days. As soon as I acclimated them and placed them in my tank however they opened up immediately and looked great. I know it can take some time to acclimate the corals but I was just surprised to see they looked great the first day but closed up the next. A few of the polyps are open but the majority are closed. Should I give it a few more days and then maybe add some more flow to them? I currently don't have any direct flow on them.

 

[malacoda]

The don't need a lot of flow. My first suspicion would be lighting. Some zoas prefer higher light, some like lower light.

Any idea what the PAR is in your tank at the level they're at? It would be good to know how much light they're getting from that a80.

If you don't have the means of measuring the light levels in your tank, my first suggestion would be to try reducing the light intensity for a couple days--either by turning your light a bit lower or, if they're on a frag plug, moving the zoas to a part of the tank that gets less light, and see how the respond.

 

[hmc520]

The don't need a lot of flow. My first suspicion would be lighting. Some zoas prefer higher light, some like lower light.

Any idea what the PAR is in your tank at the level they're at? It would be good to know how much light they're getting from that a80.

If you don't have the means of measuring the light levels in your tank, my first suggestion would be to try reducing the light intensity for a couple days--either by turning your light a bit lower or, if they're on a frag plug, moving the zoas to a part of the tank that gets less light, and see how the respond.

So if I’ve seen some par readings for the a80 and at full blast it gets about 115 PARs or so. I have it on a low setting so I’d imagine it’s only getting about 30-50 PARs based on the intensity. I’ll give it a shot with some lighting and see how that works over the next few days.

 

[cain720]

My tank is infested with vermetids, and my corals really don't seem to mind. They really only release their webs when I stir up the sand, and even then the zoas only get slightly irritated.

At this point I've just accepted them as part of my CUC, and the worst part about them is how they poke me when I'm rearranging rock.

I second the idea of lowering the light intensity on the zoas. For what it's worth, zoas were my first coral, and they took several weeks to acclimate. Although looking back, I'm sure my water chemistry was terrible.