urchin/snail sperm

[krestonc]

so i did a 15 gal water change in a 75 gal system. i used water from a different source than usual. as i was getting the last five gal in, i noticed what i'm guessing was sperm discharging from an urchin. i then noticed a similar discharge from a trochus snail.
i have read that this is both bad and good. (from different sources)
anybody have any insight or opinions?

 

[Elysia]

Water changes can bring about breeding events in snails. I suppose that some inverts may spawn when stressed (you would need to confirm this; a drastic change in water params could bring stress.) If stress did result in spawning, then I could see where someone may equate spawning with being "bad." Most people consider invert spawning events to be little more than nutrients coming into the system -- if you have corals, they can likely use these nutrients; otherwise, they need to be exported like all other nutrients or they will grow algae or nitrates.