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Desert Fish
08/22/2004, 12:02 AM
Actually two questions;
Anyone still not using a refractometer?
Since I never go to LV LFS has anyone checked the water when bring home a new fish/coral?

TippyToeX
08/22/2004, 01:15 AM
:) I use a refractometer but I broke it so I must get another.

I've checked ATMII. It was about 4 months ago and it was at 1.019. I don't bother most times because I am a slow to acclimate most fish/coral. More concerned with the change in pH so I do test that every time.

jdieck
08/22/2004, 01:17 AM
Most fish will come in water at 1.018 to 1.020. Inverst like star and snails will come in 1.024 to 1.025 and most corals at 1.023 to 1.024

EvilInSin
08/22/2004, 02:08 AM
Still not useing a Refract here, but going to change that soon I ordered one from dr fosters & smith

Shak
08/22/2004, 02:16 AM
jdieck: Um, im sorry to disagree but your statement couldnt be further from the truth. There are no "standards" when it comes to specific gravity during shipment, and lfs are notorious for not monitoring specific gravity. That kind of broad, catch-all answer, is what gets new people into trouble with their systems.

I, like Amy, am most concerned with rapid PH changes as opposed to the salinity of the water. I do, however, test both before I start the acclimation process. ATM has tanks at 1.018 to 1.024, both fish and corals are in each system, granted this is one of the worst, but all or most lfs move so much water through their systems it is never a wise decision to trust what they tell you it may be.

Use common sense, always check the water your new fish/coral come in, and above all, acclimate slowly.

Amy: you broke ANOTHER refractometer? Or have you still not replaced yours from before? Note to self: dont let Amy borrow my refractometer :D

the Undone guy
08/22/2004, 02:39 AM
how the heck do you break those things?!

Desert Fish
08/22/2004, 10:51 AM
The reason I asked is to confirm a suspicion. I know from personally checking that all the wholesalers I deal with keep fish at 1.017 - 019 ( usually at the low end ) and corals at 1.022 - 024. Ph always above 8.1 ( easy to maintain with the water turnover in their systems and very sparse feeding)
After a lot of experimentation I found that most fish tolerate only a .002 rise in s.p./24hr easily and without stress. Since lowering my incoming isolation tanks to 1.020 over a year ago I have had 0 parasite problems. Ph may be an additional problem with LFS' water.
On refractometers - A few months ago I had a chance to do a mass test of over 15 plastic meters (seachem and forty fathoms) of various ages. I lined them up on the customers' tank and every one was different! The readings ranged from 1.017 - .026. Actual reading was 1.030 by refractometer. Two of them happened to be mine so I checked them again 2 months later and the discrepency was different so you can't "calibrate" them.
Instead of a plastic s.p. meter write little numbers on a pair of dice and give the a toss - all you have to lose are your animals.

All refractometers are not created equal. - check them before you buy!

opihi
08/22/2004, 12:51 PM
I agree with all of you, but i do want to clarify one thing...

this is a refractometer (http://www.marinedepot.com/md_viewItem.asp?idproduct=CP2113)

this is a hydrometer (http://www.marinedepot.com/aquarium_test_kits_seatest_hydrometer.asp?CartId=)

when i compared my refractometer to my deep six hydrometer, i found that my hydrometer was high by .002. i would recommend that all serious reefers invest in a refractometer because the plastic hydrometers suck IMHO.

TippyToeX
08/22/2004, 02:27 PM
Jeff, I still haven't replaced the one I broke form awhile ago. :D
Bob, it was very easy! Droped it, cracked the facing. It was done for.

LVfishguy
08/22/2004, 03:20 PM
well as far as systems are concerned. We keep our tanks at .022-.024 and my corals at .026.

jdieck
08/22/2004, 03:27 PM
Shank:

There will always be exceptions to any rule, one thing I am certain, the first time I find that a dealer sent me a coral at a salinity of 1.018 that was the last time I bought from them.

On the other hand I agree that PH is even more critical as due to the wastes in the bag if later aereated the PH can swing significantly, in any case the conclusion that everyone seems to agree is that proper aclimation at least with fish takes survival a long way toward healthy specimens.

Desert Fish
08/22/2004, 11:50 PM
Just to clarify - WHOLESALERS in LA keep stock tanks at .017-.019 ostensibly to inhibit parasite outbreaks. If an LFS tries to acclimate them to a .022 - .o23, along with ph changes, this can causes high stress and possible parasite outbreaks.
This is another good reason for using isolation tanks and slow acclimation at both the LFS and buyer level.

TippyToeX
08/23/2004, 12:17 AM
Originally posted by Desert Fish
. This is another good reason for using isolation tanks and slow acclimation at both the LFS and buyer level.

Well said, and I could not agree more. :)