Zoas healthy but smaller than normal?

[Synergy]

Hi Everyone,

So I have a tank that is primarily zoas and every frag I add seems to shrink in size. The zoas open, grow, are just as colorful as when I buy them but the actual polyps seem to get smaller. Has anyone heard of this before?

The lighting is 2x24w PC, (1) 10K AND (1) 50/50 plus 3x3w Blue LEDS.
I run the PC's from noon - 9pm, LEDs are on from noon - midnight.

Water Parameters are:

Nitrate: 0
Ammonia: 0
Ca: 460
Alk: 11

One fish and an emerald crab, some hermit crabs also. None of them bother the coral. Have dipped and never found any nudis or other pests. Check at night and don't see anything but pods. Have some spaghetti worms around some of the colonies but since this is a tank wide thing I don't think that is the problem.

I do water changes every 2 weeks with Red Sea Coral pro. No skimmer. Have filter floss, chemi-pure, some phosphate sponge. I checked for stray voltage about a month ago, nothing.

I have another tank with a 70W MH (a 20k ebay bulb, got good reviews on RC). I have moved 4 different types of zoas from the 70W MH to the PC tank and they have all gotten smaller. I moved some purple deaths from the PC tank to the MH and they got bigger?

Like I said they zoas aren't dieing or melting or anything. They look great and are growing pretty well, except for the smaller size. Anyone have any ideas? I would guess it has to do with the lighting but I would have guessed the zoas in the 70W MH tank would have been smaller.

 

[A. Grandis]

Probably your tank is not mature enough or you are doing too much percentage of water changes for the size.
Try to keep 10% for water changes every 2 weeks, or per month, if not too many fishes.
Try to remove the ChemiPure also.
I would have a skimmer. That way you won't have to do so many water changes, or less percentage.
Water changes are great when you have lots of fishes/food.
Smaller tanks can't handle large amounts of water changes very often.

Even if you go to the water changes every month, it will still take a while (months) to see the results. The longer you wait to change, the longer it will take for the zoas to get better.

Keep the Red Sea salt. I think it's one of the best!!! Make sure you mix well before introduce into the system for the water changes and do that slowly.

Another thought: every zoa species are different and they'll prefer different type of environment (light/water motion...).

Good luck!

Grandis.

 

[Jarred1]

It could also be from flow, when they don't get that much flow they expand more. When they get more flow they stay smaller with longer skirts.

 

[Synergy]

It could also be from flow, when they don't get that much flow they expand more. When they get more flow they stay smaller with longer skirts.

Flow is a Korallia nano 425gph and the stock nanocube return pump. Very little rock so the flow isn't blocked too much.

The skirts aren't long. Actually, the skirts seem to shrink also. One frag I purchased had nice long skirts at the LFS but after a few weeks in the tank the skirts got much shorter.

 

[Synergy]

Any other ideas?

 

[acpoweradapter]

Do you have any pictures of it? Before and after?

 

[MrHarvard]

It could be numberous things. The flow, the lighting, and the position of where you have them (how close or far from the light). Did you get all of them from the same place? Where were they located in the sellers tank and under what kind of light. I always ask the buyer what kind of flow and light they have been under. Good luck and post some before and after pics if you have them. also how long after you put them in is this happening? Maybe they are just adjusting still.

 

[Synergy]

Do you have any pictures of it? Before and after?

It could be numberous things. The flow, the lighting, and the position of where you have them (how close or far from the light). Did you get all of them from the same place? Where were they located in the sellers tank and under what kind of light. I always ask the buyer what kind of flow and light they have been under. Good luck and post some before and after pics if you have them. also how long after you put them in is this happening? Maybe they are just adjusting still.

I'll try to get some pictures, next week. The zoas have come from a bunch of different tanks. Some were under just VHO actinics, others MH and LED.

 

[caudill187]

Many Zoas are smaller in higher alkalinity, higher light. I have a zoa/paly tank that I have kept the alk from 5 to 11 at times (over two years or so) and the polyps are bigger (and do better in general) at alk below 9.

 

[Supernova26]

Try moving them around in the tank every couple of weeks and see where they liked better.

 

[Synergy]

Many Zoas are smaller in higher alkalinity, higher light. I have a zoa/paly tank that I have kept the alk from 5 to 11 at times (over two years or so) and the polyps are bigger (and do better in general) at alk below 9.

Interesting, finally a suggestion that I can actually test. I will test the alk of both the tanks and see if their is a difference. The tank with MH lights was originally started with Reef Crystals salt but I use the same salt for both tanks though. I know the tank with the small zoanthids does have high alk always between 11-12. The other tank has LOTS of coraline growth so its possible the alk is much lower in that tank. Thanks for the suggestions.

Try moving them around in the tank every couple of weeks and see where they liked better.

This isn't just one or two colonies its the whole tank. I also have frags of the same zoas in different locations in the tank and they are all small. Plus many are growing directly on the main rock structure so I cant move them.