most adequate salinity question

[macs2015]

i recently started my 40G tank, so far its only FOWLR but i do hope to get in some shrimps and anemonies etc. not sure if i want corals though. anyways. my lfs (which i trust dearly because they know more than anyone i know) says that i should keep the salinity at 1.018 and 1.019 if i have fish only. because that way a lot of parasites and germs are inhibited by the low salinity. they showed me and the whole store has all tanks set at 1.018. and everything seems great. so i'm wondering if i get inverts or anemones do i have to raise my salinity? what would happen if the salinity is too low? how would that affect corals etc.

 

[michaeltx]

fish can tolerate a lower SG and it will help in keeping parasites at bay but when you start to deal with inverts and corals the SG needs to be closer to 1.025-1.026 its more in the range where they do the best. some can not tolerate the lower SG at all and it can cause alot of problems later on some it will kill them.
HTH
Mike

 

[lexluethar]

While I agree with his thought pattern, I personally wouldn't do a setup like that. For two reasons. One you will have a lot of cleanup on your hands and it will become more difficult to keep your Nitrates low. Why? because at that low of SG you will not be able to keep hermit crabs, snails, and other inverts that would be cleaning up your tank every day. So you will have to watch your feedings a lot more closely, scrape algae off your glass more often, and you will have to ensure that you have enough flow and mechanical filtration to pickup and uneaten food.
Another reason is you should be quarantining your fish anyways. So even if you purchase a fish w/ a parasite like ick you can treat the fish yourself. While I do understand his philosophy, I personally wouldn't do it. Parasites can be negated in your DT by properly QT'ing your fish and treating them if needed.