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FAQs about African Red Knob Sea Star (Protoreaster linckii)

Related Articles: Sea Stars, Brittle Stars, Asterina Stars, An Introduction to the Echinoderms:  The Sea Stars, Sea Urchins, Sea Cucumbers and More... By James W. Fatherree, M.Sc.

Related FAQs: Seastar Disease 1, Seastar Disease 2, Star Disease 4, & CC Star Disease/Health, Linckia Disease, Sandsifting Star Disease, & Sea Stars, Sea Stars 2, Sea Stars 3, Sea Stars 4, Sea Stars 5, Brittle Stars, Seastar Selection, Seastar Compatibility, Seastar Systems, Seastar Behavior, Seastar Feeding, Seastar Reproduction, Seastar Disease Asterina Stars, Chocolate Chip Stars, Crown of Thorns Stars, Fromia Stars, Linckia Stars, Linckia Stars 2, Sand-Sifting Stars,

Starfish      3/27/15
Woke up to this, my red knobbed sea star missing a piece of its body, levels are fine and salinity is at 1.022,
<... too low>
and starfish has been active and happy for the last week.
<This species rarely lives in captivity>

Unsure of the cause or if this is signs of disintegration, and if so I'd like to know so I may remove it so it does not kill off my stock. My
tank is 29 gallon half moon tank.
<Too small...>

I was told by my local hobby store that it may be an energy from my snowflake eel
and that it may heal over however, the starfish has positioned its self in this odd way and has been extremely sedentary today compared to its usual liveliness.
A second orange mark has also appeared hard to see in the photo but it's just between its legs
Anything than can be done, what should my next course of action be? -
<.... read here: http://wetwebmedia.com/StarDisDiagF.htm
and the linked files above. Bob Fenner>

Re: Starfish      3/27/15

Sorry, typo they said it could have been a bite from the snowflake eel who was messing with it.
<No.... see/READ on WWM re Echidna nebulosa... Don't "bite" echinoderms...>
I read the page but none of them are dealing with a red knobbed sea star,
<Actually; all does.... your Protoreastor linckii (USE the search tool on EVERY page on WWM) is falling apart like all the others gone over there. Environmental, ongoing stress... a goner>
and I don't have access to hospital or quarantine tank to store it in while I'm observing it. I read that someone placed their starfish in a bucket to observe it. Is it doomed to die?
Can it survive the night so I may place it in better care?
<Unfortunately; highly unlikely. BobF>

Red knob star fish... dying; rdg.     5/12/14
Why is my star fish doing this? He is laying with his belly facing up an exposing his stomach area on the bottom of my tank. I tested my Ph, ammonia, nitrate an nitrite an all levels are good. Please send me as much
info as possible so I know what to do.
<Something not well here... could be easily something/s you don't, there are no tests for; and/or internal issues... MOST Asteroids don't persist...
for various reasons... You may search, read re on WWM... there ARE better species; ones that historically live longer. Just put Red Knob Seastar in the search tool on any page on WWM. Bob Fenner>

Re: Abrasion on banded hound shark... actually... Not... typical Seastar death     10/28/13
<Shea>     Hope all is well.   I need some info on an issue I am having with my African Red Knob Sea Star (Protoreaster linckii).   I have noticed over the last few months that he seems to be fading in color on the red areas.   I have had him for over a year and he has been fine.  Seems to be behaving normally and eating.   I just am not sure what could cause the change in the Red Knobs turning to a pinkish color.  Do you know what this could be from.
<Yes... just search on WWM re the common or scientific name... Toss in the word health or disease if you'd like. B>
 All param.s are good and my nitrates are now in the 20-25 range which is the best they have ever been since I have had him.  Thanks for the help Mr. Fenner. 
Fw: Abrasion on banded hound shark...

P.S.    I tore through your site but could not find anything similar but if you have a link to something on your site that would be great.  Thanks.
<You'll find it soon. B>

Question- Orange Knobby Starfish    4/15/12
I noticed my orange knobby starfish eating my Staghorn coral crab.
<Mmm, unusual that it should be able to catch it, but not that it would eat it>
 It has never eaten one of my living inverts before that I've noticed but we did have a clam mysteriously die.  Could he have done that? 
Also, is it common for this type of starfish to eat living things in the tank?
<Oh yes. Bob Fenner>

Starfish and frogfish compatibility, using WWM -10/26/08 Hi, <Greetings> I have an African Knobbed Starfish (the large red and grey knobbly one), which I am keeping with a warty frogfish and some soft corals. I don't mind if it eats the coral, as they are younger bits that came from my main tank from larger corals that are doing well and reproducing lots and so can keep replacing them. <Mmmm, this species doesn't consume such> But I am worried the starfish may eat the frogfish as he is obviously quite slow moving and sits on rocks and/or the sandy bottom. <Nor Antennariiform fishes unless they're dead> We thought the starfish would be a good addition for the frogfish tank, as we are struggling to find something that is compatible with the frogfish as he eats anything! The frogfish's tank is a 1.5 foot <Too small...> long (but linked to the 5f foot main tank, to keep the water quality better), so we can't put big fish in there. So: 1. Do you think the starfish is likely to eat the frogfish? <No> 2. Do you have any suggestions of what could be put in with the frogfish and starfish (if safe). <See WWM re> 3. What are the best things to feed the starfish? I tried direct feeding some lance fish but it didn't eat it. Thanks, Cheryl <Ditto. Bob Fenner>

Shrimp/Starfish Compatibility 02/14/2008 Hello WWM crew! <<Hello, Andrew today>> I had a question about compatibility between my starfish and a scarlet skunk cleaner shrimp. I actually have two starfish, a chocolate chip and also a red knobbed in my FOWLR tank. This morning, I couldn't find the cleaner shrimp. Using a long net, I (gently) lifted up both stars and sure enough my chocolate chip had him. The shrimp was whole (no bites anywhere) and the star had him in his grips but the shrimp was mangled by any means, it was just dead. I don't know if the shrimp simply died during the night and the star was passing by and came upon a free meal, or if the star actually killed him. <<These are quite good eaters really and will prey on slow moving inverts. It could be possible that the shrimp was injured and could not move, already dead or just caught un-aware>> I haven't been able to find anything about chocolate chips eating shrimp, but before I get another I just wanted to make sure I wouldn't be adding it in vain.
<<Under normal circumstances, this is not an issue which would be common place with a cleaner shrimp in my opinion. The red knobbed starfish ( Protoreaster linckii ) is more likely to prey on inverts and corals and even other starfish as they get bigger>> I appreciate your thoughts. As always, thanks for the great information and help. Mike P. <<Thanks for the questions. A Nixon>>

Red Thorny/Knobby Star (Echinaster echinophorus) Best Left in the Ocean.   2/22/07 Hi Bob, <Hi K.B.!  Mich with you tonight.> My compliments to you and your staff for the great job you do and your dedication to education with regard to marines. <Thank you for your kind words.  It is nice to be appreciated.> Quick identification question for you.  Attached are a couple pics of a red thorny/knobby star that I'm told is reef-safe.  I've searched the web for this star and have found many similar but cannot confirm its species.  Would you be so kind as to identify the species and whether or not it is reef-safe? <Does appear to be Echinaster echinophorus which has a poor survival rate in captivity.  It is believed that the natural diet is comprised of sponges, but have read reports of it eating meaty foods in captivity.  Reports to be reef safe, but short lived.>    Many, many thanks.
<You're welcome!  -Mich>
Re: Red Thorny/Knobby Star (Echinaster echinophorus) Best Left in the Ocean.   2/22/07 Thanks Mich.  I found what I thought was this star in my research, and I trust now that it was judging by the information you provided here. <Glad to help.> Thanks again.
<You're welcome.  -Mich>

Red Knob Sea Star / African Sea Star    4/9/06 Hello,   <Hi there>   Great site!    <Thanks>   I am interested in getting a Red Knob Sea Star / African Sea Star / Red General Star...are these all the same star?    <Both names are applied to a few animals, mostly Protoreastor lincki>   Can I have shrimp and crabs with this star?    <Yes... as long as they themselves are compatible... this Seastar will consume other sedentary, sessile invertebrates>   Can I have a red Coris wrasse with this star?    <Should be able to>   Thanks a lot!  This star is the best looking star I have seen so far. <Are gorgeous animals... for larger, stable/established marine systems. Bob Fenner>   

African Red-Knob Starfish Hi, I have just treated my tank for ich with Rid-Ich+ by Kordon. In the process the corners of my tank where the silicone seals were have turned blue. I have tried scrubbing clean but it won't come out. Any ideas on removing the stains? <Can't be removed practically...> If not it's a pleasant coloration to the tank. <Good> My main question is that I am getting a African Red- ">Knob Starfish and am worried that on its travels around the tank it might soak up the Rid-Ich through the silicon and be harmed. <Mmm, nope. Once absorbed... transformed... gone. You might want to run a bit of activated carbon, Polyfilter to assure yourself> What is your insight on this? The starfish is an expensive investment and I don't want to have it die due to the Rid-Ich in the silicone or anything left over in the dirt. Also, my tank doesn't get much algae, what would I need to feed the starfish, or do I need to? Thank you. <Mmm, a few important things to impart to you... One, I would not treat your livestock in your main/display tank (for reasons that are likely obvious to you now), and this star is not a good choice for most all types of marine systems...http://www.google.com/custom?q=African+Red-Knob+Starfish&sitesearch=wetwebmedia.com Bob Fenner>
Re: Rid-Ich
 Just a quick follow-up. Do you think Rid-Ich is still present in the sand?  <No... please read here re Malachite Green: http://www.wetwebmedia.com/malachitegreen.htm and the Related FAQs linked above> Also you say """One, I would not treat your livestock in your main/display tank (for reasons that are likely obvious to you now)""" What reason's are those, just the coloration? <...... no my friend... please read on WWM re... the loss of nitrification, kill-off of other beneficial life...> The coloration I can deal with, its actually quite unique, but could anything else have been harmed or soaked up the Rid-Ich and might harm future fish? I have a Bio-wheel type filter and am worried that the bacteria culture on it may have been harmed even though the Rid-Ich label says it won't. <Incorrect> What is your take? Or am I just being a worrier? <Good to be a worrier> I have a damsel and a clown in there and they are doing excellent as of now, no more signs of ich and things are looking good. I am going to do a partial water change today and then let the tank cycle for about a week before I decide on the starfish. I read the link you sent me, thank you. I do not have any live coral in my tank or anything that the starfish could harm, just a damsel and a clown who are living happily together. <Ah, good> I was thinking about getting a chocolate-chip star, ~$5 to test things out before jumping in and getting the ~$40 red-knob (which would really put a nice touch to my tank-- red starfish, orange/white clowns, black/white damsel and aqua blue corners thanks to Rid-Ich, haha) After reading a lot the chocolate and there- knobbed are very similar, and I would much rather lose the Chocolate than the red-knob. Your opinion on my proposed venture would be greatly appreciated. Thanks again.  <All of what little I know is posted. Bob Fenner> 

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