Mail ordered corals and the salinity of the water they came in is pretty high - is that common?

[Just John]

I just got a shipment of corals from Cherry Corals. They all seem very happy and zoas were open even when they arrived. But, the specific gravity of the water they came in is 1.031. I checked twice and made sure the refractometer was calibrated both times. Is it common for places like this to keep it that high?

 

[GoReefin]

I just got a shipment of corals from Cherry Coral. They all seem very happy and zoas were open even when they arrived. But the specific gravity of the water they came in is 1.031. I checked twice and made sure the refractometer was calibrated both times. Is this common?

Usually from my experience LFS and shippers run their systems a bit on the lower end when it comes to salinity.

 

[Garf]

I just got a shipment of corals from Cherry Corals. They all seem very happy and zoas were open even when they arrived. But, the specific gravity of the water they came in is 1.031. I checked twice and made sure the refractometer was calibrated both times. Is it common for places like this to keep it that high?

Are you calibrating using RODI?

 

[Azedenkae]

I just got a shipment of corals from Cherry Corals. They all seem very happy and zoas were open even when they arrived. But, the specific gravity of the water they came in is 1.031. I checked twice and made sure the refractometer was calibrated both times. Is it common for places like this to keep it that high?

I agree with @GoReefin, 1.031 seems to be very high. LiveAquaria for example houses their corals at 1.021 and 1.024, iirc. To me this is just really odd. What does your aquarium measure at?

 

[Just John]

I calibrated using calibration fluid to 1.026. Right now my water is close to that.

 

[Garf]

I calibrated using calibration fluid to 1.026. Right now my water is close to that.

It would be very odd to get coral in that much saltyness. I would do a DIY cal solution just in case yours is messed up. If it still reads the same then, no, it is not common for shops to be throwing salt away.

 

[Just John]

Could that much change during acclimation be an issue. I have done it over about 1 hr.

 

[Apollo7235]

My refractometer came with instructions to calibrate to 0 using distilled water. Maybe give that a go and try again?

 

[Just John]

My refractometer came with instructions to calibrate to 0 using distilled water. Maybe give that a go and try again?

Thanks. I just checked now. It reads 0 with distilled water.

 

[Garf]

My refractometer came with instructions to calibrate to 0 using distilled water. Maybe give that a go and try again?

They usually read too high when calibrated with RODI. The refractometer could read 1.026 but it’s really 1.021 for example.

 

[Apollo7235]

They usually read too high when calibrated with RODI. The refractometer could read 1.026 but it’s really 1.021 for example.

Right, I'm not talking about RODI, but the distilled water you can buy from the store.

 

[Apollo7235]

Thanks. I just checked now. It reads 0 with distilled water.

Well darn. Sounds like the water was just extra salty that day You could give Cherry a call and double check with them. Honestly, if the corals seem happy and healthy, I wouldn't worry too much, but then again, I am super new to the hobby so I can't speak much from personal experience. I hope it all works out for you!

 

[ScottR]

No it shouldn’t be that high. If you’re positive your refractometer is correct, call or email them to ask. But if your corals are doing ok, then I wouldn’t worry about it. IME, LFS usually run lower than what most people keep tanks at to save costs.

 

[Just John]

They seem fine and are starting to open again in my tank now. I was really curious because, as everyone has said, that seemed really high to me. Thanks for the input everyone!

 

[Azedenkae]

They seem fine and are starting to open again in my tank now. I was really curious because, as everyone has said, that seemed really high to me. Thanks for the input everyone!

Good luck with the corals! If you do end up contacting Cherry Corals, let us know how it goes. I am super keen to know how this came to be.

 

[Garf]

Right, I'm not talking about RODI, but the distilled water you can buy from the store.

Tap water ain’t got much salt in either lol. I predict low tank salinity, Alk, Cal, Mag etc etc.

 

[Apollo7235]

Tap water ain’t got much salt in either lol. I predict low tank salinity, Alk, Cal, Mag etc etc.

No, tap water may not have much salt in it, but some tap water may contain enough dissolved solids to cause a refractometer to register a falsely high reading... Our water comes from our well and good Lord.... It has so much iron in it that, without our filtration system, it literally turns everything brown. Tap water is unreliable, in my opinion, whereas distilled is pretty much a reliable constant.

You can buy a DS meter to measure the dissolved solids in your tap water to verify whether or not it's suitable for this use, but I feel like the one or two bucks for a gallon of distilled is more cost effective.... Unless you're like me and have a DS meter you already use to monitor your RODI system

 

[Garf]

No, tap water may not have much salt in it, but some tap water may contain enough dissolved solids to cause a refractometer to register a falsely high reading... Our water comes from our well and good Lord.... It has so much iron in it that, without our filtration system, it literally turns everything brown. Tap water is unreliable, in my opinion, whereas distilled is pretty much a reliable constant.

You can buy a DS meter to measure the dissolved solids in your tap water to verify whether or not it's suitable for this use, but I feel like the one or two bucks for a gallon of distilled is more cost effective.... Unless you're like me and have a DS meter you already use to monitor your RODI system

I think you’ve misunderstood me. Calibrating a refractometer with Freshwater is not ideal and could be giving the OP a high reading in the bought coral water when in fact he, and others by the sounds of it, are running there tanks at a lower salinity than they think.

 

[Just John]

I think you’ve misunderstood me. Calibrating a refractometer with Freshwater is not ideal and could be giving the OP a high reading in the bought coral water when in fact he, and others by the sounds of it, are running there tanks at a lower salinity than they think.

I know that wasn't for me, but I did not recalibrate it. I just looked to see if it read 0, which it did.

 

[Patientman]

Someone please help me here … seem to remember (from a lonnnng time ago) that temperature could affect salinity (or am I hallucinating) … if the water heated up or cooled in shipping … could that have caused a salinity swing?