FAQs about African Red Knob Sea Star (Protoreaster linckii)
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,
Disease, Sandsifting Star Disease,
Sea Stars 2,
Sea Stars 3,
Sea Stars 5,
Seastar Disease, Asterina Stars,
Chocolate Chip Stars,
Crown of Thorns Stars,
Linckia Stars 2,
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.
I was told by my local hobby store that it may be an energy from my
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
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:
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...
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
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
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>
Orange Knobby Starfish
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
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
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
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>>
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
for you. Attached are a
couple pics of a red thorny/knobby
star that I'm told is
searched the web for
this star and have found
many similar but cannot
species. Would you be
so kind as to identify
the species and whether
or not it is reef-safe?
<Does appear to be
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
<You're welcome! -Mich>
Re: Red Thorny/Knobby
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
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-
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
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:
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-
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>