how do I do a water change?

[inuyasha_lover_21]

How do I add the new pre-miced salt in the tank? does the salinity have to be lower or equal to the salinity in the tank?

[leebca]

This is a good question. In fact, few old aquarists give it much thought. The advanced and experienced aquarists take it for granted. So here is one way to perform a water change:

1. Make sure you're using proper source water (see: WATER - Source and NSW). If there is any doubt as to the quality of the source water, test it. Artificial salt manufacturers who recommend using tap water as the source water are wrong. The variations on tap water around the world make it such a wide range of ingredients that it isn't consistently reliable enough for source water for the marine aquarium. Get more information about the downside to using tap water here: Chemistry and the Aquarium

2. Mix the source water, preferably using a submersible (inside aquarium) pump (not an aerator). The water should move up and down in the mixing container, not around in a circle.

3. Add the artificial salt, in the quantity required to get close to the marine system's specific gravity.

4. Mix the salt according to the salt manufacturer's directions (as to how long to mix). (NOTE: The salt manufacturer should know how best to mix their water, however studies have shown that the most stabilized water is achieved after about a week of mixing. This extended time is connected to gas exchange and the chemical reactions going on in the water with the gases from the air.)

5. After mixed, check the specific gravity of the prepared water. [NOTE: If the salt mix is not properly blalnced to provide the proper calciium, alkalinity, and magnesium, now is the time to bring that into balance with the chemistries in the marine system. More on this here: What is Water Quality.] The specific gravity of the new water should match as closely as you can with the specific gravity of the water it will replace. Adjust the new water by adding a little more salt, or adding some source water. If a lot of salt had to be added (more than 2% of what you've already added) then go back to 4.

6. When the specific gravity of the new water matches the marine system water specific gravity, measure the pH and temperature of the marine system and the new water. Adjust pH and temperature of the new water to that of the marine system water. (NOTE: This is one of the places of the biggest common error -- the pH adjustment. The pH of the new and old water must be extremely close -- to within 0.05 pH units, if possible). The temperature of the new water should be no lower, and can be up to 1.5F higher than the marine system water.

7. Remove the water from the marine system. You can take advantage of siphoning in order to clean out detritus/debris around in the display tank, sump, and/or refugium.

8. Add the new water to the marine system.

After the above, it is important to replace evaporated water with distilled water (if you have a small aquarium), RO/DI, or deionized water. Maintain a constant specific gravity of the marine system, a constant pH in the proper zone, and a constant temperature.

Hope this helps.

[Reefland]

Everything about the new water being added should match the current tank conditions. This includes temperature, salinity, pH and it is even best to adjust for calcium and alkalinity as well.

[inuyasha_lover_21]

Thank you both for being so generous to help me with my question.

I been telling alot of people about this site. This is the best site I have been on and the best forum

[leebca]

Thanks for your kind words.

[Derpeder]

1st POST!!

Okay does anyone out there keep like a 50 gallon garbage can filled with water change water heated to the right temp and that has the same gravity(can be adjusted due to evaporation once your ready for a water change) as your tank?

I was thinking about doing that but are there any negatives in doing that? I'd keep a powerhead in it for continues watermovement.

That way you can just double check all the levels and do the water change.

[leebca]

WELCOME TO REEFLAND!

Good job on the first post. Post more!

For my 100 gallon water changes, I use two 55 gallon heavy duty Brute containers (from Grainger) on dollys.

I follow the above mentioned procedure and then hold the water until I need it, or use it as soon as it's ready -- either way. Just before using it, I mix it and test all the parameters, adding heat if needed.

The circulating pump gives off some heat, so it acts like a mild heater during the mix process. I finish off the temperature with two 250 watt heaters if they are needed. Hence, if I'm going to use the water after mixing is complete, by the time the temperature gets higher, I shut off the pump.

I store water like this for no more than 5 days at a time, since I do weekly water changes.

[Derpeder]

So with a 100 gallon you do a weekly water change....how many gallons per water change?

And could you keep the water for like 2 weeks and get two water changes out of it?

[leebca]

I use about 80 gallons of it at a time for the main system. I use 40 gallons at a time for my quarantine tanks. I use about 5 gallons a week for incidentals, including rinsing out fish foods. So, my water doesn't sit long.

Some water I've had sitting does start 'activity.'

As mixed and prepared water sits, it encourages microbial activity. Even water in the dark will develop some. You can try it for the two weeks you mention, but if you see discoloration of the water or fine particulate matter, you should not do it again.

[ralphie16]

I use about 80 gallons of it at a time for the main system. I use 40 gallons at a time for my quarantine tanks.

I do daily 10%-20% water changes for my QT tanks. But I use the water from the display tank as the "new water". I figured this water is clean since my other fish are living in it and it would help the new fish get used to the water conditions it will be living in soon, as well as to make the final acclimation as painless and easy as possible.

Does this make sense? Or am I better off using "virgin" water? lol

[leebca]

As stated in the Quarantine Procedure thread, you can start the QT with display tank water. After that, all water changes need to be new salt water (virgin).

You may think the display tank is 'clean' but there is never any guarantee. So don't risk using display tank water.

See this:
A Fish Quarantine Process

[inuyasha_lover_21]

Well Ii did my first saltwater water change. Kinda stressful but I never give up. The water dropped from 81F to 73F fast so I ran downstairs and got some distilled water heated up with the same specific gravity as the tank and saved it. Its back at the right temp and the anemone is doing great.