The Green Death & Larger Fish, Ophiarachna comp.  1/12/2008
Hi WWMedia Crew!
<Andrew>
I'm a huge fan of the site, as well as the Bob and Anthony's books. You've helped me a great deal, as I've moved forward with my first tank.
<Glad we've been of assistance to you>
I'm hoping you can help me again. I'm looking toward the somewhat distant future of my tank and had a question, concerning the green brittle star's appetites. Would larger fish, e.g. lionfish, morays or Marine Bettas be in jeopardy? (These are what I have set up, to date.)
<Not nearly as much as smaller, more easily captured fishes>
Of course there's the Betta, who I know enjoys caves... once he has reached adult size would he be OK with the green brittle star?
<A question of relative size...>
The Betta comes first for me--he's got nothing but personality, and I brought him home and intend to care for him anyway. I want to be sure he's safe.
I have a 90g tank with around 120 lbs. of live rock, a 20g and a TurboFlotor protein skimmer, if that helps sketch out the logistics.
My levels are usually around 77 degrees, 1.023 SG, 0 ammonia, 0 nitrites, <10 nitrates, pH 8.2. No inverts so far--aside from the ones that showed up on my live rock. I'm sticking mostly with a FOWLR setup.
Thanks. I'm truly grateful for all you do...
ATH
<There are other Ophiuroid/brittlestar species... I might look into others. Bob Fenner>

Compatible Clean-Up Crew - 08/30/06
I have a 30 gallon reef w/:
Fish: 1 flame hawk, 1 false Perc Clown, 1 cherub angel
Corals: tons of assorted mushrooms, hard (Frogspawn, candy cane), & soft (finger & umbrella leathers)
Other: serpent star, live rock
All inhabitants have been in the tank for at least 2-3 years (some 8+ years).
<<Excellent!>>
I have not added any livestock in a few years & it's time to risk rocking the boat & add something new.
<<...with caution>>
Since my current clean-up crew consists of just the serpent star I was looking at adding a package for general maintenance & to add some variety to the tank, but I know that the flame hawk limits my options.
<<A bit, yes>>
I'm considering some Astrea snails,
<<Little bulldozers>>
red hermits
<<Opportunistic omnivores...and snail killers>>
(I've found that the bigger ones hold up pretty well around the hawk) and possibly one or more of the following:
- another serpent star:
<<Excellent detritivore>>
they are cool, but will another fight with the one I have?
<<I have always found Ophiuroids to be quite compatible between both inter- and con-specifics>>
- a Coral Banded Shrimp OR 3-4 peppermint shrimp: I know they likely wouldn't get along together, & that the CBS would have a better chance w/the flame hawk, but don't know how aggressive he would be w/other inhabitants.
<<Can be very aggressive>>
Or should I completely forget about any kind of shrimp w/ this setup?
<<Normally, I would recommend Lysmata amboinensis and/or Lysmata debelius as the most beneficial (cleaners) and the least destructive of the commonly available ornamental shrimp.  But the presence of the hawk fish does pose a threat to these shrimp>>
- One or 2 emerald crabs:  I think they would fair reasonably well w/the flame hawk, but don't know how aggressive they might be toward other existing/proposed inhabitants.
<<Have been known to attack/kill fish>>
Any comments on my plans are greatly appreciated - I'd rather be informed that something is a bad idea before anyone gets eaten.  Suggestions of other critters to add in place of anything on the list are also welcome.
<<My opinion is to exclude the crabs (all are too opportunistic for my taste) and go with some snails (Cerith and Nassarius species get my vote) and maybe another serpent or brittle starfish.  The Nassarius snails and the starfish are excellent detritivores, the Cerith snails feed upon algae/diatoms without knocking your corals about or falling on their backs and dieing/fowling the water>>
Thanks,
Kim
<<Quite welcome.  EricR>>

SCAVENGERS
>Hello,
>>Hello, Marina here.
>I have a 75 gallon saltwater fish only tank with crushed coral for substrate.  Please tell me what type of scavengers would be best to help clean up uneaten food?  Something that is easy to maintain.  Also, how many would you recommend?
>>Serpent stars.  You could add three or four easily.  I cannot recommend anything else without knowing what you have for residents (hermits, shrimps, and so on, may be eaten by wrasses, triggers, large angels).  Best of luck!  Marina

Detritus Eater
Bob,
I have a 13 gallon CPR Micro Reef tank with live rock and live sand. I have a couple of dead spots between and behind the rock where some detritus is collecting. Right now it doesn't appear to be a big problem because the skimmer is doing a good job of keeping nitrate levels down and algae blooms non-existent. Actually, the only algae I have in this tank is coralline and it's thriving. I have done some research on different detritus eaters (hermits, cucumbers, serpent stars), but all of these seem to have risks involved. 
<Yes>
I have yet to see an article about hermits that doesn't say they kill the snails or eat the coralline. The cucumbers are ok except I have a power head in the tank for water circulation. I don't want the cucumber getting sucked in and having to completely redo my tank. Serpents have been notably given the reputation of eating fish, snails, and shrimp. As a matter of fact I went to the LFS last night and saw a green serpent feasting on a snail in the display tank. 
<This species of Ophiarachna is a huge predator...>
Is there any alternative you can suggest to help with this problem? 
<If this were my tiny reef, I'd add a small submersible pump and leave "it" as it is...>
I can't add any fish. I already have my quota there. I saw from FFX that they are saying that tapestry snails eat detritus. Is that true?
<Hmm, yes.>
Thanks for your help, Chad
<You're welcome. Bob Fenner, who knows what creatures dwell in your rock, sand... and would leave this "detritus" work to them... and the increased circulation.>