what are the effects of high salinity on sps?

[Chris82]

Was hoping for some input or experience on this topic. Cheers.

[Slyguy00]

How high are we talking? Iv had mine up to .031 by accident for a few weeks without any issue. Sps don't mind the high salinity, from my experiences its everything else in the tank that has a hard time with it.

[LoJack]

Originally Posted by Slyguy00

How high are we talking? Iv had mine up to .031 by accident for a few weeks without any issue. Sps don't mind the high salinity, from my experiences its everything else in the tank that has a hard time with it.

I agree, SPS will be the last to notice the salinity. I recently just had mine drop low (1.017) because my refractometer was out of calibration ... and it was the fish that showed the first signs that something wasn't right ... I never would have noticed because my SPS were showing no signs of stress at all.

[asylumdown]

Originally Posted by LoJack

I agree, SPS will be the last to notice the salinity. I recently just had mine drop low (1.017) because my refractometer was out of calibration ... and it was the fish that showed the first signs that something wasn't right ... I never would have noticed because my SPS were showing no signs of stress at all.

Really? I've had exactly the opposite experience. I went out of town for a week when my tank was about 5 months old. I didn't have the ATO system set up yet so I had the R/O float switch plumbed right in to the sump. When I left I set the skimmer cup to empty right to a sewer drain. Something in the tank made the skimmer go nuts while I was gone, and when I got home my specific gravity was 1.018. I think 4 corals out of 15 survived, fish were unfazed.

[Marlin65]

Too high will kill your fish first. I had mine at 31 one's and killed off one of my fish. SPS showed no problems at all.

[MitchM]

Lower salinity is harder on corals than higher salinity.
Try to keep the salinity around 35 to 38 ppt.
Much variance beyond that and the coral will spend a lot of it's energy maintaining it's internal ionic balance.
If the coral spends too much energy maintaining that balance, it will die.

[LoJack]

Originally Posted by asylumdown

Really? I've had exactly the opposite experience. I went out of town for a week when my tank was about 5 months old. I didn't have the ATO system set up yet so I had the R/O float switch plumbed right in to the sump. When I left I set the skimmer cup to empty right to a sewer drain. Something in the tank made the skimmer go nuts while I was gone, and when I got home my specific gravity was 1.018. I think 4 corals out of 15 survived, fish were unfazed.

I think this is probably due to how fast your change took place. Your salinity dropped to 1.017 very quickly due to the skimmer malfunction, mine has dropped over the course of a year as my refractometer slowly went out of calibration over a long period of time.

I am now trying to bring it up equally slowly to prevent any issues with the tank. I am topping up with saltwater every other day to slowly increase the salinity without shocking anything.

[MitchM]

Lojack, how did your refractometer drifting out of calibration cause your salinity to drop?
When you did water changes, did you add less salt to each batch?