Hydroids and sponges

[rottface4]

Now I am aware that these are not typically dangerous in our tanks, but perhaps more of nousiance. But in some cases if left unchecked they can reach epic proportions. I just wanted to start a discussion about different hydroids and toxic sponges that maybe found in our aquariums and what we can do to rid them of our tanks. I myself am not an expert in dealing with these but I know of a few. The Brown Hydroids resemble a small feather duster, with a small brown tube and a brownish to greenish polyps. They have a pretty potent sting for corals, and if they encroach on a coral they may kill it off. I haven't found a way to erradicate them from a tank yet.

this image was borrowed from nano-reef c est ma

The other hydroid I am familar with is the digita hydroid. These have a spagetti worm like tentacle with little fuzzy bump on it. They sway around in the current. They also have a nice sting to some corals in the tank. Some good insight on these from Melev although I can't find it from the Id page I can only find it with the search function. But that might be that I'm not very smart or something.

 

[chad508]

i have what i believe to be chicken liver sponge. it seems to like high light and will also kill off corals. i have lost a few zoo's to this sponge and have not found a way to rid the tank of it. i did put in a cherub angle hoping he would eat some but i don't believe he does. i have also pulled rocks out and scrubbed them to only have the sponge come back in a week. my only other option is to pull the rocks out and just let them dry out and then recycle them . if you have any info please let me know.

 

[FatCow]

I have always thought those in the picture are apthsia.

 

[TimTen]

I am in the middle of killing my tank due to a digitoid hydroid infestation. I have a 24 nano-cube that I over fed, and them being filter feeders loved this. I saw one on a coral and being new it took me several weeks to identify it. Once I found out what it was I tried to attack them with a Kalk mix, it worked if I covered the base up. I wish I blasted it the first night I saw it. The problem was that I waited to long and they where already all over. I also made a mistake of doing a crushed coral bed which they love. I found a product online called Hydrox, for Sea Horse tanks. However it is not intended for use in reef tank and they told me it will harm them. So far, I'm into day 3 of the treatment and all my corals are suffering. I will let you know after the 6 day treatment which ones make it and what dies. Just hoping for the tank not to crash. They really come out at night and since I don't have a good camera I wasn't able to take there picture.

My addvice if you see a Digitoid Hydroid in your tank, get up right now, get some Kalk and cover the whole thing.

while looking into hydroids I found reports that Keyhole limpets eat certain type's of hydroid, I believe like the one's in your picture. The problem is there are several reports of them eating coraline. I would also cover those with a kalk paste.

 

[rottface4]

chad - If I remember correctly I believe tiger cowries will eat the chicken liver sponge.

Fatcow - An aiptasia can look very similar to the photo shown when small. However the hydroids will stay small and have a hard tube they can retract into, where as aiptasia do not.

Aipatasia Image borrowed from reefkeeping magazine

 

[FatCow]

ah...okay
thanks rottface4

 

[chad508]

i will have to give that a try shawn thanks

 

[greg_monterey]

Ok, I have a big infestation of the digitate hydroids. Can someone tell me why it is absolutely necessary to eliminate them? I have watched them touch my acros and clam and multiply over the past couple of weeks but I see no ill effects at all. When they touch the corals there is no change in polyp extension or anything. In any case, it is way beyond the point of target killing them as they are pretty much everywhere in my 150 gallon.

 

[GobyJohnKenobi]

I had a colony of hydroids on a particular rock in my tank.

They seemed to thrive when the rock was placed towards the bottom in an area of low flow where most of the detritus in the tank seemed to settle.

I moved the rock to the top of the tank right under the output from the protein skimmer and the disappeared. Perhaps the increased light, flow and much lower nutrient levels did them in.

 

[wld1783]

I have the hydroids everywhere. My main concern is that they eventually cover the rocks near the bases of the SPS and slowly starve the bases of light and flow. Some of my SPSs have either spawned or more likely released some polyps and attached them to the rocks covered with the hydroids. Interesting the new polyps cleared the hydroids and have started to grow. Competition for space seems to be natural and for now the little ones are winning!

I would like to see a way to lessen them but for now they are more of a nuisance rather than a problem.