Specific Gravity Question

[celacanthr]

I gauruntee you that if you took 2 blue linkia's that were in the same health, and put one in a tank with a sg of 1.021, and one in a tank with 1.026, and both tanks had the same amount of LR, then the one at the higher sg would live longer, and be healthier.
Same with most other echinoderms
and tunicates
and nudibranches
so do you fluctuate your salinity?

 

[aufishman]

Originally Posted by CELACANTHr
I gauruntee you that if you took 2 blue linkia's that were in the same health, and put one in a tank with a sg of 1.021, and one in a tank with 1.026, and both tanks had the same amount of LR, then the one at the higher sg would live longer, and be healthier.
Same with most other echinoderms
and tunicates
and nudibranches
so do you fluctuate your salinity?

Do you have any scientific data to back this up? because unless you do it's all conjecture on your part. I've seen plenty of echinodems and tunicates which thrive in esturine conditions were the salinity fluctuates greatly. Yeah, some organisms are going to do better at a higher salinity, but 29 ppt is plenty high for most. And no I don't fluctuate the salinity of my tank. I keep it around 28 ppt.

 

[celacanthr]

Why don't you fluctuate your water, like the coastal waters do?
Gimme a few minutes, and I will give you some sources.

 

[redleg]

marines will all b ok at 1.021 and lower if the sg is kept constantly at that level ,what you are now do.ing is fluctuating your sg that will harm them. there is nothing wrong with a sg at 1.021 - 1.025. the keeping of all marine creatures is about water parameters mess with them if u like but it affects everything E.G temp-ph-calcium level-alkalinity-orp-,plus at a lower sg u have more dissolved oxygen in your water. i think the sg is ok but then . TEL :happyfish

 

[celacanthr]

Sorry, my comments about why he didn't fluctuate his water, was more sarcastic, then anything else.
I just thought it was weird that if he keeps his animals at 1.021, because it happens in a minority of the world, and during a minority of the year, then why doesn't he fluctuate his sg, which happens in a minority of the world during a minority of the year?

 

[aufishman]

Originally Posted by CELACANTHr
Sorry, my comments about why he didn't fluctuate his water, was more sarcastic, then anything else.
I just thought it was weird that if he keeps his animals at 1.021, because it happens in a minority of the world, and during a minority of the year, then why doesn't he fluctuate his sg, which happens in a minority of the world during a minority of the year?

That was not my point. You said that all reefs have a significantly higher sg than 1.021 (which equates to around 29 ppt salinity). That statement is BS.
Originally Posted by CELACANTHr
How is 1.021 fine? All oceanic reefs have a significantly higher specific gravity than that. Obviously the reefs (other than human destruction) do wonderfully at that sg. So why would we put them at a lower sg?
My point is that 29 ppt salinity is more than adequate, and you can go significantly below that as long as the salinity remains constant.

 

[celacanthr]

I still don't believe that that is true. I really have nothing to support me. I am sure if I wasn't lazy, I could find some sources, but this argument isn't important enough for me to do so.

 

[kimc]

I agree w/CELACANTHr. I keep my SG - 1.025... FYI

 

[lion_crazz]

Well to back up CELACANTHr, there is a huge article on Reef Keeping Magazine about why fish and inverts will live much longer at a higher salinty. The writer points out that they can tolerate a lower SG, 1.021, and live in it for quite a while, but he actualy did scientific research to show that fish and inverts live better and longer when they are given a SG closer to their natural habitat.
Again though, I know this to be factual so it is not worth my trouble to look up the article just to prove you wrong.

 

[aufishman]

Originally Posted by lion_crazz
Well to back up CELACANTHr, there is a huge article on Reef Keeping Magazine about why fish and inverts will live much longer at a higher salinty. The writer points out that they can tolerate a lower SG, 1.021, and live in it for quite a while, but he actualy did scientific research to show that fish and inverts live better and longer when they are given a SG closer to their natural habitat.
Again though, I know this to be factual so it is not worth my trouble to look up the article just to prove you wrong.

whatever floats your boat dude.

 

[xrobbx03]

i finally have got my tank up in SG i have it a 1.026.

 

[wangotango]

you guys going back and forth sound like an old married couple

i keep mine around 1.023-1.024 and everything seems happy.

 

[ophiura]

Originally Posted by AUFishman
Do you have any scientific data to back this up? because unless you do it's all conjecture on your part. I've seen plenty of echinodems and tunicates which thrive in esturine conditions were the salinity fluctuates greatly. Yeah, some organisms are going to do better at a higher salinity, but 29 ppt is plenty high for most. And no I don't fluctuate the salinity of my tank. I keep it around 28 ppt.

These echinoderms that live in estuaries are quite specialized. I promise you that not all echinoderms can tolerate estuarine conditions for long perios. And while they may not die immediately, they will not do as well long term as when they are kept at higher salinities, and the mortality rate would be relatively higher in the population (though if they can leave and get to deeper water, many will). Echinoderms as a class are classic stenohaline animals. You can have mass mortalities of echinoderms simply due to heavy rainfall in enclosed bays (see papers by Dr. John Lawrence).
The average salinity in the ocean is 32-35ppt. So that is a good salinity value to aim for, IMO. If you want to do something else, that is OK...but if you have difficulty with invertebrates then the first thing I would look into is raising the salinity.