Question about PH and waterchange

egkid

egkid

AC Members
Jul 28, 2007
218
0
0
37
I'm setting up my 45 gal and decided to mix my own water with lfs brought RO water ($.59) vs using their saltwater ($1.39). I'm using instant ocean salt mix for now (I was going to use reef crystals but it was out of stock), I figured I'd use this water to do waterchanges on my other tanks (probably this week only) currently there is only the salt water in the tank with a heater and power head, no substrate or rock. Heres my concern the ph on the water I mixed is 8.4 the ph in my other two tanks is 7.8 could I run into problem if I use the water to do a wc? By the way the substrate in my other two tanks is live sand not crushed coral.


(Cliff notes) The water I want to use to do my WC with has a ph of 8.4 the ph in my tanks is 7.8.
 
I'd be more concerned that the water in your tank has a low PH. Do you have any surface movement?
 
I'm changing 5 gallons out of a 29 gallon tank.

For surface movement I have my cascade 500(115gph) return line almost pointed straight up half an inch under the surface of the water.
 
7.8 is within the acceptable range. Many tanks running calcium reactors have a regular pH around that same amount. The only concern is if it drops much lower at night.
 
Also if you add the Ph 8.4 too quickly and you have fish in the 7.8 a rapid ph change can be harmfull. You may want drain off the amount then add half of what you are going to for the water change, wait awhile, then add the rest.
 
snailrider said:
Also if you add the Ph 8.4 too quickly and you have fish in the 7.8 a rapid ph change can be harmfull. You may want drain off the amount then add half of what you are going to for the water change, wait awhile, then add the rest.
Click to expand...

Again, that depends upon the amount changed. If it is not above 20% or so (if what I calculated is correct), it shouldn't change more than .15, which is within acceptable ranges. Even then, the carbon dioxide should react with it rather quickly, making the change relatively minimal.

Out of curiosity, egkid, have you tested your alkalinity? I just want to make sure it is due to carbon dioxide (usually the case) and not simple low alkalinity. Also, how long did you allow the water to sit? It should be lower than 8.4 once it equilibrates with the atmosphere. It almost sounds like you didn't let it mix and react long enough.
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom