how to change water?

it says i have to change 25% of my salt water every month. but how do i do it? does that mean i have to take out 25% of my current salt water and put in fresh salt water??

 

So you have never done a water change before? Not even in freshwater?
If so, you will need a few things, minimum on that list are a 5 gal bucket, siphon, spoon, .5cup measuring cup, hydrometer, dechlorinator(if not using RO water). So recommened items would be a larger mixing vessel, powerhead, and heater.

First use the siphon to remove the gallonage per 25% or whatever percentage you choose, into the bucket(s). This will A. give you a place to put this removed water before you dump it and B. tell you how many gallons you have taken out.
Once you have removed the water, its time to fill, you use SALT water not fresh water.
The most simplistic way to do it is put rougly 2 1/3 cups of salt into the five gallon bucket, fill with water and as you are filling stir VERY VIGOROUSLY until the salt is completely dissolved. Then pour into tank. Like I said this is the most simplistic way to do it.
A better way is to add the appropriate salt and water(preferrably RO) into your mixing vessel, add the heater and power head and run both over night to reach the proper CO2/O2 ratio, to let the salt completely dissolve and achieve the proper pH.

Use your hydrometer/refractometer to test the water you mixed to make sure the specific gravity is where it should be!
If using tap do not forget a dechlorinator or you can have some issues!!
Good luck and keep those questions coming!

Happy reefing and cleaning!

 

yes allways check parematers befor changing. and how much water evaporates. if i go a month with out topping off 25 to 30% would be gone and salt level off the charts. also how long has your system been setup? this will factor in when scheduling whater changes.

 

with all the fishes in it?

 

how many gallons is your tank?

 

i think it's roughly 13 gallons, like 43 litres.

 

do you have any pics?

 

so you say fish is this a reef or just fish.......any live rock?? also how long did you cycle this system. also do you have a sand bed? cause if so be verry carful not to stir up.

 

yea, im quite a beginner at this. i've started my tank for about a month plus for now. it's just a small tank, 2 feet. i'll attach my pic.

 

With a 13G tank, you will want to change only about 2-3 gallons. You will need at least a hydrometer to check your specific gravity (SG) and salt level. You want the SG at 1.024 or so. If it is higher, you want to first add plain reverse osmosis fresh water to get it to 1.024, then continue with the water change. Another option would be to make the new saltwater less salty to bring your tank to 1.024. That is a better way, as it is less shocking to your fish, but is more complicated.