Starfish information

[Hp1836]

So recently I had to give up my starfish due to him starting to eat coral. Was told he was reef safe and had him over a year without thought or problems. All of a sudden I saw him eating a lepto then a day later a monti. Completely killed them both. I gave it to a local store but it got me thinking.
1 I never found out exactly what type he was so any ideas on that?

2. I would love to replace him with one of the blue linkia but last I heard they were near impossible to keep long term. This was 5+ years ago I looked into them last so if anyone woth long term experience with them would be able to share it would be appreciated.

 

[kchristensen8064]

Look up Giant-spined star (Pisaster giganteus). That's what it looks like to me anyway.

 

[Uncle99]

Bumps or spines = bad news.
Starfish don’t last long in captivity, better left in the sea.

 

[ISpeakForTheSeas]

1 I never found out exactly what type he was so any ideas on that?

Given the coloration, a species from the Echinaster (Othilia) subgenus like Echinaster sentus or E. spinulosus would be my first thought; either way, they should be similar dietarily:

For clarification here, Echinaster (Othilia) spinulosus (and closely related species like Echinaster (Othilia) echinophorus) in the wild are thought to primarily feeds on sponges, tunicates, biofilms, detritus, and dissolved organic matter (DOM). They can also filter nutrients directly from seawater through their skin. Anyway, they are known as both opportunistic predators and scavengers. In captivity, many sea stars - including Echinaster (Othilia) spinulosus - are known to eat unnatural diets, consuming things like shellfish (including shrimp), bivalves (clams, mussels, oysters, etc.), small starfish (like Aquilonastra spp. - known in the hobby as Asterina stars, though those are species of a different genus in the Asterinidae family), and even sand dollars.

Echinaster (Othilia) spinulosus is known to be a long-lasting species for aquariums, which indicates to me that there is a good chance they're dietary needs are more readily met by things like bivalves, unlike Linckia spp. and similar, which tend to die off within a year even when regularly offered things like clams to eat.

With regards to Echinaster sentus specifically, from what I’ve been able to find, they eat bivalves (clams, mussels, scallops, etc.), sponges (they accept some species that have chemical defenses against fish, but it seems they prefer those with little to no chemical defenses period), possibly some anemones, and possibly other sessile (immobile) inverts too (so it may at some point go for corals, or it might not - there's not much information available on the diet of this species).

2. I would love to replace him with one of the blue linkia but last I heard they were near impossible to keep long term. This was 5+ years ago I looked into them last so if anyone woth long term experience with them would be able to share it would be appreciated.

They're still pretty much impossible to keep:

Personally, I currently recommend against trying to keep a tropical, true starfish (Asteroid) species, particularly biofilm-feeding species, except for Aquilonastra stars.

That said, if you're really determined to try keeping them anyway, I'd strongly suggest setting up an Aquilonastra farm, a cryptic refugium to farm sponges, and possibly a colonial tunicate farm as well (all of these should be separate from the Linckia's tank so they can't get to the farm and ruin the "crop") - the Linckias feed on these (they presumably emulate biofilms to some degree), and the most successful Linckia keeping I've seen have always involved at least one of these aspects (typically the Aquilonastra stars).

With Aquilonastra stars alone, I've seen people keep them 2-3 years; with the cryptic refugium sponges involved too, the longest I've heard is ~4 years. Still not good by my calculations, but arguably acceptable if they really only live a decade.

For more info, click my username in the quote above and it'll take you to the post that quote was pulled from - you can ask if you have more questions.

(Edit: To add, sometimes people with very large tanks get lucky and their tank can support their biofilm-feeding stars, but it's definitely not a guaranteed thing, and from what I've seen it fails much more often than it works.)