Go Back   Aquarium Advice - Aquarium Forum Community > Saltwater and Reef > Saltwater Fish Only & FOWLR
Click Here to Login

Join Aquarium Advice Today
Reply
 
Thread Tools Search this Thread Display Modes
Please support our sponsors and let them know you heard about them on AquariumAdvice.com
 
Old 01-01-2007, 08:14 PM   #1
Aquarium Advice Newbie
 
Join Date: Sep 2006
Posts: 5
Send a message via AIM to corinnasue
Salinity and specific gravity- goin down?!

I have a question about salinity and specific gravity. Here is my setup:

30 gallon bowfront
Inline heater. 76.5 degrees
Fluval 204
Airstone
Powerhead
Crushed coral Substrate
Red Sea Hydrometer

My hydrometer is currently reading 1.017. Goal range = 1.020

I seem to be losing salt? why? (no leaks beleive me, I checked)- topping off with only fresh water.

1. When I change water should I be replacing with saltwater at 1.020? I was told by my Fish Dealer replace only freshwater.
2. How do I safely raise the salinity? I have a choc chip star in there and I know he is sensitive to salt change. Do I pull water out of the tank, add salt and return that water?

Thanks in advance for your help. PS- this seems to be a common problem for me prior to water changes. SOS
__________________

__________________
corinnasue is offline   Reply With Quote
Old 01-01-2007, 08:23 PM   #2
Aquarium Advice Activist
 
Join Date: Dec 2006
Posts: 186
You should be topping with freshwater. Are topping off the exact amount? I have a line in my sump with a piece of tape?

What kind of hydrometer--They are known to be inaccurate sometimes.

2-No, you can slowly raise you SG by topping off a very little less slowly over a few days until you move up a few. Go as slowly as possible.

With no corals it is not as crucial to have salinity on the higher end, however I still recommend a refactometer to make life a little easier for you.
__________________

__________________
Tomd is offline   Reply With Quote
Old 01-01-2007, 08:45 PM   #3
Aquarium Advice Newbie
 
Join Date: Sep 2006
Posts: 5
Send a message via AIM to corinnasue
I think you are asking about my water change? Let's say I take 3 gallons out (for easy math)- i put 3 gallons back in - yes. The water I am putting back in is fresh water. Shoudl it be salt water set to the same salinity as my tank instead?

My top offs are to a predefined level on my tank, so I am not dumping in more fresh water than water that has evaporated.

2- To clarify- you are saying to let the water level drop to increase the salinity?
__________________
corinnasue is offline   Reply With Quote
Old 01-01-2007, 08:48 PM   #4
AA Team Emeritus
 
Join Date: May 2002
Location: Virginia
Posts: 2,256
Send a message via ICQ to fishfreek Send a message via AIM to fishfreek Send a message via MSN to fishfreek Send a message via Yahoo to fishfreek
This is the logic to take with adding water to your tank.

If YOU take water out then you must put saltwater back in.

If you replace water with out having first removed it then put freshwater in.

When you remove water your removing salt and water so you must add saltwater back to replentish the salt and water you took out.

When water evaporates (you do have evaporation dont you?) the salt remains in the tank and only the water leaves so you must replace the lost water with freshwater to balance out the salt and water ratio.

If you do not have evaporation then your tank is sealed to tightly. No evaporation also means you have very poor air/water gas exchange resulting in lower oxygen levels.
__________________
Remember dont tap the glass, your fish will think you're an idiot -Anonymous mother

Check out our articles area. 30+ Aquatic articles for your enjoyment
Are you in or around the Shenandoah Valley area? If so click here to join our regional forum.
fishfreek is offline   Reply With Quote
Old 01-01-2007, 09:05 PM   #5
Aquarium Advice Activist
 
Join Date: Dec 2006
Posts: 186
And I was talking about topoff. A piece of tape or something in the tank you use to refrence so you know how much evaporated.

It was just a guess, but that may have been how your salinity got lowered without water changes.
__________________
Tomd is offline   Reply With Quote
Old 01-01-2007, 11:36 PM   #6
AA Team Emeritus
 
Devilishturtles's Avatar
 
Join Date: Jul 2003
Location: Frederick, Maryland
Posts: 8,544
Send a message via Yahoo to Devilishturtles
In a nutshell, your fish dealer told you wrong. I think fishfreek summed it up well. You should be adding saltwater in when you do a water change. Freshwater when you top off. That is the reason it is going down.
__________________
-Lindsay

Live in the Western MD/West Virginia/DC Metro Area?
Join our very active regional forum Here

Like the advice someone just gave you? Add to their reputation! Click on the balance icon underneath their username and let them know.
Devilishturtles is offline   Reply With Quote
Old 01-01-2007, 11:39 PM   #7
Aquarium Advice Activist
 
Join Date: Dec 2006
Posts: 186
OMG!!! I did not even read that! I was thinking topoff the whole time
__________________
Tomd is offline   Reply With Quote
Old 01-02-2007, 10:37 AM   #8
AA Team Emeritus
 
roka64's Avatar
 
Join Date: Mar 2006
Posts: 13,860
Send a message via AIM to roka64 Send a message via Yahoo to roka64
I agree:
Top off with fresh water.
PWCs you will have to replace the SW you took out. If you have inhabitants, in the tank, you can raise the salinity by adding slightly higher salty PWCs.
__________________
Age is relative, you are only as old as you act....of course, this works in reverse....

Questions loved, heeded advice greatly appreciated!

Vote for AA
Good reading about:
Nitrogen Cycle
Fishless Cycling
Need more help?
Articles
Acronym List

--Scott
roka64 is offline   Reply With Quote
Old 01-03-2007, 11:27 AM   #9
AA Team Emeritus
 
Join Date: Sep 2005
Location: VA
Posts: 3,391
Send a message via Yahoo to tecwzrd
sg changes should always be done slowly (especially with sea stars) but you can also increase sg by alternatively topping off with well mixed SW one day and FW the next until you get your sg where you want it. I'd aim for an sg closer to 1.022-1.025 IMO.

SW should be mixed 24+ hours in advance before adding to the tank preferably with a power head. The newly mixed SW should match the ph/temp/sg of the main tank as closely as possible to avoid osmotic shock to your tanks stock.

Swing arm hydrometers like yours are notorious for getting out of calibration (especially if ever dropped). I'm sure your sg is lower if you have been taking out SW and replacing with FW but as already mentioned a refractometer is much more accurate/reliable.
__________________

__________________
-Micah-

If you haven't figured it out yet I like to BOLD links :P

Vote for AA at Aqua Rank
tecwzrd is offline   Reply With Quote
Reply

Tags
gravity, salinity, spec, specific gravity

Please support our sponsors and let them know you heard about them on AquariumAdvice.com

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Salinity and Specific Gravity movinweight Saltwater & Reef - Getting Started 4 06-15-2006 05:58 PM
Specific Gravity bj5z25 Saltwater Reef Aquaria 2 07-14-2005 10:30 PM
specific gravity chatcher Saltwater Reef Aquaria 4 01-23-2004 12:14 AM
Safe Specific Gravity and Salinity omcnair Saltwater Reef Aquaria 1 03-25-2003 04:46 PM







» Photo Contest Winners








Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -4. The time now is 07:43 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.