I have a question in regards to Oyster Shells and wondering if there would be any benefit to putting them in a sump. I have posted this question in a couple of other forums to get a broad range of thoughts, still waiting for replies. I read somewhere that they have a water purifying quality and was wondering if this was the case and would they be beneficial in any other way.
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Tank Type: Mixed Reef
Display: 125G (140lbs LR, 3" Sandbed(175lbs))
Sump: 20G (2" sb)(cheato) & 8G subsump (6"sb)(10lbs LR)
Skimmer: ER RS-135 and saline solutions unit
Return: remote fuge with mag pump
Overflow: Lifereef
Heater: black strealth
Phosphate Reactor: bag of GFO
running Carbon Media 24/7
RO: Costco
Salt: IO
Light: 72" 3x175 MH and 2 60" VH)
Sump Light: 7x12
arrr, oysters> u know the greeks were cultivaing these suckers as far back as the 4thcent BC!
mark, oyster shells alone will do nothing, if your talking about oysters with animal intact then yeah, they are water scrubbers!
u would need alot of them to be worth while & personallyi would have them in enclosed plastic cages if i were to use them! and futher more i would look into the pacific species of green lip mussels or pacific oysters as another alturnative!<crap spell tonight sorry>afew scotches under the belt already! but these species grow quickly> reaching maturity in as little as 18months or so! but in saying that, if im not mistaken>which i prob am> blue point is the common species in the states? ok, nothing to see here, move along!!!!!
ok a couple things spring to mind!!!
they will take up trace elements as they grow, which needs monitoring like any other coral!
they respond the same way as coral! hot spots in the ocean result in coral death, & likewise story in bivalves! although i might add, contradicting what i just wrote...........they tend to spawn in walmer weather geographicly, my saving point is its seasonal to that location(which makes it less contradicting...lol)! but if someone knows the approx temp where the scales tip, then id like to know!
sex> shock kiddies! this is actually a bigger issue, they reproduce externally so>oysters broadcast their gametes (or gamites, i cant remember) in the water with leads to the display! to be honest im not sure on the negative impact, but it could be an irratation to the other more sensitive corals!
once again individual sexing identification per species of bivalve are dictated by temp! most start as males in the spat stage if that gives u an indication on sexual dismorphism...lol
spat if u didn't know is youngling oysters or mussels,& when u cultivate them funny enough its called spat cultivating! anyways...on with the show.......!
u have the ethical debate on your hands....when do i eat them! when keeping them, u will notice they go though 3 distinct cycles! if u want to know more i can give u a brief overrun! but once again! its an ethical debate! only cause anything we add to the tanks usually have immunity from our mouths! me> i dont get suck punched into that debate! i dont eat clams, but i do eat oysters! given the right species, if u provide the added irratation seed, u could cultivate your own pearls! but lets stick to the cultivation for water buffering shall we! lol
well actually, oyster shells are very high in calcium. they are recommended for use in argocrete because it will better simulate the use of calcium carbonate based LR.
not sure if a sand bed of them would be a useful, but i would image it would be the same as crushed coral of the same size.
personally, the size of the grains are too large in my opinion unless you want to clean the crud out all the time
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whooohooo, kill the motor dude! u dont need a substate to keep oysters or mussles!
they bond to the medium u provide for them> hopefully a solid structure or substrate> namely Rock! never granulated substrate!
u know rob, u might be totally right! & me totally wrong! i believe MACMAN was indeed talking about the shells as a substate> man im like a total gumby!
well Macman> i squeezed a bit of information out of this water soaked brain of mine that u can store in your own useless information, concider that a freebee! lol
well oysters shells are commonly used in chicken feed, so there available all over the place... you can get them ar farm feed store, or markets that carry funny stuff like that
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hehehe no not in SD. I'm originally from AK. then moved to WA. and Grays Harbor Wa. is one of the leading oyster growing areas in the US. I worked for coast seafoods which is part of Hiltons clam chowder.... read the ingredients some day, you wont find a clam in any of the canned clam chowders except gouy duk (sp?) which is like a gianormous steamer clam, it's mostly oysters and "clam jiuce" (you don't want to know).
oyster shell was used sometime back. i have never used it, but i believe it fell out of favor because of a high count of silicate, lead, and mercury. don't qoute me on this, its was a long time ago.......and i'm just shooting off from memory.
anyways...on with the show.......!
when keeping them, u will notice they go though 3 distinct cycles! if u want to know more i can give u a brief overrun! but once again! its an ethical debate! only cause anything we add to the tanks usually have immunity from our mouths! me> i dont get suck punched into that debate! i dont eat clams, but i do eat oysters!
given the right species, if u provide the added irratation seed, u could cultivate your own pearls! but lets stick to the cultivation for water buffering shall we! 
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