pH problem

[whazzup101]

hey guys, i just got my water checked today

so far..
pH: 7.8
ammonia: 0.5
nitrite: 0
nitrate: 0

i'm a little worried about my pH though, 7.8 is my tapwater pH so that would mean that even though i have about 8lbs of crushed coral and 13-14lbs of lr the pH hasn't gone up for a week! is this normal? should i get a alkaline buffer or what do i need to do?

[schoch79]

What is the salinity of the tank? In my experience the salt always set my ph to right about where it needed to be.

[kkyyllee]

7.8 is fine no worries

[Percula9]

From the readings you posted your tank is showing ammonia. Is your tank still cycling? Do not use tap water for your make up water. How long has the tank been running?

[whazzup101]

Originally posted by schoch79
What is the salinity of the tank? In my experience the salt always set my ph to right about where it needed to be.

salinity is about 1.027 i would say.

[whazzup101]

Originally posted by Percula9
From the readings you posted your tank is showing ammonia. Is your tank still cycling? Do not use tap water for your make up water. How long has the tank been running?

yeah the tank is cycling. today is exactly one week the tanks been running.
i use de-chlorinated water for my make-up water. the water that we drink at home.

here's the thread i made when i first started the tank

http://archive.reefcentral.com/forum...readid=1182716

[whazzup101]

Originally posted by kkyyllee
7.8 is fine no worries

isn't the pH supposed to be at like an 8.3ish?

[whazzup101]

help?

[Lotus99]

It's not unusual to see pH changes during cycling. Next time you make up a batch of saltwater, test its pH.

If you don't have enough flow/movement in the tank it can also have low pH due to a low oxygen content.

Edit: looking at your tank, your pump is probably underpowered. Did you get something stronger yet?

[schoch79]

I don't know what to tell you. How are you testing the salinilty? Whatever you are testing it with are you sure it is calibrated(refractometer) or not sticking(swing arm)? It just doesn't sound right. Try like lotus said and test the ph in a freshly made batch of saltwater at your salinity. I second that if the tank is low on oxygen it could lower the ph. You can also try using an airstone in a cup of your tank water and after it's in their for a little while test that water for ph. See if it helps.

[whazzup101]

okay, what i think i'll do is get a powerhead by today. what pump is efficient though? is 100gph good for a 20g? or should i look into something more?

[ljosh]

I think you would want about 400gph total circulation, or more, depending on what you want to keep.

[whazzup101]

Originally posted by schoch79
I don't know what to tell you. How are you testing the salinilty? Whatever you are testing it with are you sure it is calibrated(refractometer) or not sticking(swing arm)? It just doesn't sound right. Try like lotus said and test the ph in a freshly made batch of saltwater at your salinity. I second that if the tank is low on oxygen it could lower the ph. You can also try using an airstone in a cup of your tank water and after it's in their for a little while test that water for ph. See if it helps.

what do you mean how i'm testing my salinity. i'm using a deep six hydrometer. the arrow is point in between a 1.026-1.028, so i'm assuming it's 1.027. there are also numbers along the side that reads ppt 16-40 and i'm at 36. ohh and when do i need to make a water change, after it's done cycling? and how much water needs to be taken out? 5g?

[bertoni]

Oxygen doesn't affect pH. CO2 will drop pH. Given that the tank is still new, the low pH might go away on its own once the decay process is done. I'd probably do 3g water changes or so.

Hydrometers are sometimes very inaccurate. This article might help:

http://www.reefkeeping.com/issues/2004-06/rhf/index.php

[schoch79]

Bertoni is right about the oxygen and co2 thing. I guess I just indirectly stated that co2 will drop PH because I assumed that if oxygen is low co2 will therefore be higher. Thus lack of oxygen could lower the ph. I guess directly this is wrong but indirectly right. Sorry if I mislead anybody.

[schoch79]

I was just looking through some books and I came across something I thought you would be interested to know. When you mix your water do you add the water to the salt or the salt to the water? If you add water to the salt the concentration of the saltwater could cause the calcium to precipitate out causing low ph. Maybe you have low calcium and therefore your ph is low.