Pardon my late response, I'm not real active on line lately, always busy. Anyhow I have freshwater, the concept of different components feeding of of and adding to a good balance is very exciting for me. Plants, inverts and fish in perfect harmony...hahaha. I have to laugh a little because nothing will every be perfect in my opinion. There is ALWAYS something to fix, adjust, compensate, clean and of course keep an eye on. I have a single (small) Asian Clam for 5 days now. I did the egg yolk mix for food and got good results, the first 3 days no movement...lol. I felt stupid thinking it was dead at first till I studied closely and noticed very very tiny opening along the shell lips for about a minute or less at a time. That was a huge relief knowing it was in fact filtering. Thank you for responding and all I'm asking is for a basic ballpark/window for lifespan I understand the many tangible elements involved including the different types. This is an awesome hobby and the hardest part for me is giving it a reasonable amount of time. Time management is a B*~′Ch!!!
Lol