I need a 30ppt salt mix, help

[Cyberpaddy66]

Hey everyone.

I need to go out and buy some Instant Ocean salt mix and was wondering if you could give me some advice before I go to the shop as I have a very limited budget and need to get just the right size packages.

I need a salt water mix of 30ppt for a small tank of about 12 litres, what would be the smallest quantity of Instant Ocean I could buy to give me this ratio of salt to water?

Before anyone starts telling me that my mix is wrong it's for a shrimp fry tank that needs to be just above 30ppt for about 30 days with possible 10% water changes every few days (not an exact science as the fry breeding is totally experimental at this stage.

I know this isn't technically a marine species but they need sea water to grow from fry to shrimp so I figured I'd ask here anyway.

What would 30ppt be if I read it on a hydrometer/refractometer?

For the whole Shrimp thread look here (http://www.aquariacentral.com/forums/showthread.php?t=132226)

[OhNo123]

loved the music. :D

[fsn77]

30 ppt equates to a specific gravity of roughly 1.022.

[Cyberpaddy66]

Thanks fsn77 (http://www.aquariacentral.com/forums/member.php?u=40231)

I have a spare brewing hydrometer lying about somewhere, would that work for a rough guide or does it have to be a specifically saline designed hydrometer?

[fsn77]

Honestly, I'm not at all familiar with brewing hydrometers, so I'm not sure how close it would be. Are you referring to a glass one that you put into the solution and then read the value at the liquid's surface?

[Cyberpaddy66]

That's the very one, I have 3 of them and only use one for my brewing.

I tried it out the other day using the guide on the package to try and gauge 1.022 and the hydrometer read between 1.020 and 1.025 which is close enough for me :D

[Sploke]

A floating triple-scale hydrometer will work, but as you probably know if you homebrew, that they are calibrated for 60 degrees F, so you'll need to adjust based on temp as well.

[Grins]

I tried it out the other day using the guide on the package to try and gauge 1.022 and the hydrometer read between 1.020 and 1.025

That is a huge difference in a marine tank, especially with an invert like a shrimp. Not sure what it would do in your situation.

[Cyberpaddy66]

That is a huge difference in a marine tank, especially with an invert like a shrimp. Not sure what it would do in your situation.

Well going by the research others have done anything from 30ppt to 35ppt is fine for shrimp fry, they all seem to be doing fine.

The water has clouded slightly but I was expecting that as I'm trying to get a strong algae growth going in the tank, I'll probably do a 25% water change before I go away for the week but I'll be worrying about the little buggers while I'm away :y220d: