Jump to content
Pic of the week


Pic of the week poll #14
Sign in to follow this  
Shahbazin

pH Lower Than Usual in Tank vs Tap

5 posts in this topic

I'm wondering what causes pH to be lower in the tank than in the tap? And if I should be concerned about this? For months, my 75. gal has run at a steady 8.0 pH (tap is 8.2), & then I tested it this week & got a reading of 7.8 pH in the tank (did it twice to be sure). Also, I just got the KH/GH test kit, & KH is also also lower in the tank than the tap - 107.4 (6 drops) tank, vs 125.3 (7 drops) tap. GH is 340.1 in both (19 drops).

 

Ammonia & nitrite are zero in the tank, nitrate was higher than usual (40, usually about 20-30).

Tap ammonia is 1.0, nitrite & nitrate 0. 

Tank temp is 72F, 4 goldfish (11-12 cm SL), heavily planted, AC 110 with filter floss pads replacing charcoal, Hydro sponge 5 PRO run by powerhead, small airstone (cleaned both filters recently, lots of squishing in tank water bucket, sponge last week, AC 110 the week before). Substrate is Nat'l Geo sand & gravel, mixed. Water tests all done with API kits.

 

 

Share this post


Link to post
Share on other sites

High nitrate leads to a lower pH.  You need to change more water.

Share this post


Link to post
Share on other sites

High nitrate leads to a lower pH.  You need to change more water.

Aha! I wondered if it was something straight forward like this - it certainly makes sense, since nitrate levels were up a bit. I'll need to modify my water change routine, then. Thanks!

Share this post


Link to post
Share on other sites

What she said :)

Share this post


Link to post
Share on other sites

Also carbon dioxide (from the natural process of your fish breathing in and out, and decaying plant matter), and tannins from driftwood will drop the ph.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×