water prep

[harday]

Sorry for the silly question, but I'm a newb and need some assurance here. I plan to use distilled water for my water changes. Once I mix in the salt and cap the jug, how long is the water then still safe to use? Does it go bad after a certain amount of time? I would like to mix one large bucket, then put it in a number of smaller jugs for each change, but I don't want to do anything wrong. Any guidance here would be very much appreciated.

[Aiptasia]

Distilled water is 100% pure water, which means it has nothing in it. That means that the water can swing acidic or alkaline depending on what you add to it. If I were you, i'd consider using a little buffer in the water before mixing in the sea salts. Kent marine makes a product called osmo-prep marine. Here's a link:

http://www.kentmarine.com/html/opm.html

 

After that, a good synthetic sea salt mix, like instant ocean, should be used to make your sea water. Some sea mixes recommend you use water in a specific temperature range so that your hydrometer readings will be accurate, from 75 to 80 deg.. I use a 5 gallon plastic bucket from Home Depot that's only been used to mix water (never used as a cleaning bucket, no soaps or chemicals ever used in it) and you can put a small aquarium heater in it to warm it if you'd like. Just suction cup the heater to the side (don't let it come into contact with the plastic) or affix it to the rim at the top.

 

Instant ocean and other good sea salts can be used almost immediately. I like to take my RO/DI water and put it in the bucket, mix in the osmo-prep, mix in the sea salts and measure the specific gravity with my hydrometer. When it's between 1.022 and 1.024, it's full strength sea water and it's good to go.

 

Any extra sea water, I usually keep for water changes. I simply remove the heater and put the plastic lid that came with the bucket on top to prevent evaporation. You can keep this extra sea water for weeks, maybe even a few months, if you need to, but since water changes (10% weekly) is a recommended idea for any reef tank, you'll probably use it up long before then.

 

It's not that hard, you can handle it. Just remember to use a thermometer and make sure that the water you're adding to the tank is the same temperature as the water in the tank already, especially if you've stored the water out in the garage or in an unheated environment.

[Shelley]

Also remember that you don't need to add salt water for evaporation top ups. As the water evaporates, the salt stays in the tank and causes the salinity to increase. Use plain RO or distilled water if it's just evap top up!

 

Use salt water to top up the tank during water changes.

 

Hope that makes sense.

[harday]

Thank your for the responses. I have read so many things that differ. Some say mix the salt and let it sit for 24 hours before using. Some say put a power head in the bucket and let it mix for 24 hours before using. Some say just mix it and it's immediately ready for use. Not only am I confused as to which of these is correct, but I also didn't know the shelf life of mixed water. For my weekly one gallon water changes, I plan to mix one 5 gallon bucket, pour it into 5 one gallon jugs, stick em in the closet, and use one each week for the water change. I just wasn't sure if I could keep a pre-mixed jug for 4 to 5 weeks before using. If anyone else has any input on what they feel is the "correct" way, I'm all ears. .

[Jim J]

The way I did it for many years is:

 

Fill bucket wit DI water.

Mix the salt into the water per the instructions on the package.

Use a power head or airstone to circulate the water for several hours.

Adjust the temp to 75-78 F with a heater.

Check the SG after about 12 hours and adjust as needed for inconsistency in salt mix. (Let set and aerate for a couple of more hours if any more salt was added.)

Check PH and adjust as needed.

Use as much as was needed for w/c.

Store unused in gallon jugs with caps, but aerate with airstone for atleast an hour and match tank temp before using.

 

For emergency w/c, I bring the water up to temp while waiting for the cloudiness to disipate. Heavy aeration to ensure high disolved O2.

 

Be sure to always aerate your water just before using it, or leave the cap off during storage.

 

Now I have a spare 10G tank in the basement that is kept FULL of ready to use SW. I only heat it long enough to reach tank temp, just before use, in order to reduce evap. I keep it covered to keep dust and other nasty out. Power head running in it all the time, air stone bubbling only while heating up to reduce likelyhood of contamination from chemicals/fumes that may be in basement. I test the water SG/PH each time I test my reef.