* EricEE says Tonight, Gregg and Saltman will be giving a talk on Coral Placement and Agression. Enjoy the chat.

Hi everyone. I know I'm not Leroy Headlee from GARF like you expected, but he could not make it tonight, so y'all will have to bear with me while I, with help from Saltman, talk about:

CORAL PLACEMENT AND AGGRESSION

As many of you regulars know, I own a 10 gallon reef, so I pay much attention to how aggressive a certain coral is, and where to place it. This also applies to larger, heavily stocked tanks, where placement can be a problem

First, we'll start with some of the most aggressive corals. These are the LPS (Large Polyp Stony) corals. Some of these are:

• Elegance Coral (Catalphyllia jardinei)
• Hammer Coral (Euphyllia ancora)
• Frog Spawn Coral (Euphyllia divisa)
• Bubble Coral (Plerogyra sinuosa)

These corals all can have fairly long sweeper tentacles, loaded with stinging cells.These tentacles usually extend at night. For this reason, I would recommend any of these or related corals well away (more than 4" if you have the room) from any other corals. Also, most of these corals prefer medium to high light, and a medium current.

Other LPS corals I would like to discuss are:

• Open Brain (Trachyphyllia geoffroyi)
• Plate Coral (Fungia sp.)

Many times, I have seen open brains on rocks. This is not a good idea. If the flesh covering the skeleton brushes a rock, this may tear the flesh, causing it to recede and die. They usually open their fullest on the substrate. These corals are usually found on the substrate of a reef tank. By the way, plate corals can let off slime loaded with nematocysts if they are disturbed. This can be a problem, as the slime floats around the tank, and eventually lands on a coral, sometimes killing it.

Next I would like to talk about SPS (small polyp stony) corals. Most of these are aggressive to the point of keeping things away from them. Due to their delicate nature they tend not to survive the stinging of the more aggressive corals. Because of these corals being somewhat defenseless they have adapted to needing stronger currents and high lighting. They tend to grow and survive much better on the top part and outer parts of the reef. In the home aquarium it is recommended that only SPS corals be kept. Not mixingthem with Soft corals or Polyps of any type. This would include anemone's of all types.Saltman has kept SPS corals and LPS corals with out any ill effects for some time. Buthe still recommends that it not be done.

Now, let's move on to soft corals.

I have observed some soft, branching corals, I assume to be Sinularia, with very long,thin sweepers. This was in a dealers tank, so I am not sure of their stinging ability. Also, leather corals will release terpenoids. Terpenoids are "chemical weapons"released in the water to claim territory, usually affecting the coral down current.As for placement, most soft corals of the leather type enjoy medium light and current.

POLYPS

There are many, many varieties of polyps, from the many different varieties ofZooanthids (buttons), star polyps (Clavalaria sp.), xenia (Xenia sp), etc. These polyps do not have any visible forms of defense, but most of it lies in chemicalwarfare between these polyps and hard corals. The polyps produce terpenoids, a type of noxious chemical, which they deposit on hard corals that brush against them, and some even release chemicals into the water. For example, there are certain species of xenia that will kill Acropora on one contact .

Placement: From what I have said here, you obviously do not want to place polypswhere they can come in contact with other corals, especially hard corals. Most of these polyps, except for buttons, thrive with high current, and medium light.

Mushrooms, (actinodiscus, ricordia sp., inodiscus sp.), are the least aggressive corals.As far as I know, they have very little, if no sting at all. Part of the natural defense of mushrooms may be that they have adapted to lower light, current, and water quality than other corals can stand, so they have little competition for space.

Finally, I would like to say a few words about anemones.

Anemones have a stronger sting than almost any coral, except for elegance and some ofthe Euphyilla corals. They can be a threat to a reef tank, since they are not sessile. They are free to roam about the tank, stinging any corals in their path. For this reason, anemones are not, in my opinion, suitable for small and/or heavily stocked reefs.But, if you must have an anemone, Bubble anemones (E. quadricolor) are probably themost suitable for a reef tank.

And that concludes my talk. I probably don't have all the answers, but feel free to askany questions you may have. Saltman will be answering any of your sps aggression questions. We will then un-moderate the channel, and you may return to the normal chat. Thank You.

Looks like thats it.

Nia> Thank you Gregg, very nice talk- very informative

thanks nia

Q: What's the actual "striking distance" of some of the corals?

Striking distance is different for differet corals, lps can go a medium distance, but some soft corals have very long sweepers. One more thing. Yes I Am has observed favia retract from contacting a mushroom other corals

Q: I was a bit confused about the recommendation of not keeping LPS with SPS???

Basically what I am saying is that if you have a number of LPS corals in your tank and they sting/attack a SPS coral the SPS coral will most likely loose. As stated I personally keep LSP and SPS corals in the same tank. I have never noticed any agression between these. LPS have long sweepers. SPS have very little sting. But due to the agressive nature of LPS corals they could cause problems.

Q: isn't the Galaxia sp. the ones with the long sweepers?

I personally have never seen Galaxia with long sweepers

Q: have you observed an interaction between a SPS and LPS and the resulting conflict for space?

No. I have had LPS corals and SPS corals in my tanks for a number of years with no agression between them.

Just another comment on sweepers: Just because a coral seems to have very short or notenticles, does not mean that they cannot have sweepers at night. example: even open brains can have 2-3" sweepers and also corals like Favia can have 2"+ sweepers

Q: what corals do you have in you 10 gal tank, and what are the battles for space that you have observed?

I currently have a pearl bubble, open brain, plate, and clove polyps. I had a hammer coral a few months ago. at night, it sent out sweepers going all over the tank definately not a good choice for small/heavily stocked tanks After i added the polyps, i did notice my LPS corals closing for about 3 days after the addition Also, i had to devote almost a whole half of the tank to the pearl bubble, due to it's tenticles at nigth

Q: I was wondering if anyone has tried removing the sweeper tentacles from a coral that is stinging another, and how quick they took to grow back?

I have not removed sweepers, but after the addition of the hammer, it took about a week to form sweepers.

Q: was the closing of the LPSs after the additon of the zoanthids the only negative effect noticed?

Yes, LPS only closed. no deaths or anything

I would like to clear something up. LPS corals, due to the nature, tend to be a larger type coral. This is why thier "Sweepers" are more agressive. SPS corals "USUALLY" dont have sweepers as long due to where they grow at normally. By stating that you not house SPS and LPS corals in the same tank. this is just a warning so that if something bad happens, it might help you understand

Q: where should Fungia sp. and open brains be placed if have no substrate

Fungia can be placed directly on the glass open brains must be placed on rocks in that case, because they have a cone shaped skeleton, they would fall over when placed on the glass

I have my open brain on a rock, because my fungia coral takes up most of the space on the bottom...I just have to make sure that only the skeleton is touching, not the flesh.

Great talk Gregg and Saltman