pH trouble

[salty420]

I am so totally frustrated! I've had to accept the fact that the pH in my FW tank will always be high no matter what I do. It's about 8.2 out of the tap and no matter what I try to do to lower it it stays at 8.2 in the FW tank. So I think, well, that's good news for the new SW tank I set up... but NO! The pH in my SW tank is 7.8! How is that possible? My ALK is high, higher than my dip stick test will read. WTF is up (obviously not my pH!)?? My poor FW fish would probably LOVE the nice 7.8 level! GRR I'm so mad... :mad2: Will the pH go up after my cycle? I'm at the point now where my ammonia is 0 and at about 1 ppm nitrite. I am seriously so mad about this...

[NapoliNewJersey]

I think there is an additive you put in your water and it could raise your Ph ... I'm new to this but I could be wrong but I think it's an easy fix.

Hopefully someone on here will answer quick with better info.

[Snoogans]

I was having a similar problem with my salt water tank and added some pH Buffer that helps stabalise pH at 8.2. I've had some success with this but to maintain am needing to do it weekly

[TropicalNorth]

Increased CO2 levels can result in a low pH.
Do you have a good water flow on the surface ie a powerhead near the surface? What's your turnover rate?
If you have glass lids you could try taking them off and see what happens.

[5xevy]

pH buffer should work. pH also tends to lower at night so if you have a refugium you can keep that night on all night (or some keep it on 24 hours/day) and that will help stabilize it too.

What kind of salt do you use? Also, this is a pretty decent link on pH and water hardness:

http://www.drhelm.com/aquarium/chemistry.html

I use pH buffer myself and the refugium light helps to keep it stable during the night.

[fsn77]

There's multiple possible reasons for low pH.
How long has your sw tank been running? It doesn't sound like all that long since you asked if it'll go up after the cycle. The pH in our reef tank took about 2 months to really settle in and stay consistent.

This article may be helpful to you:
http://www.reefkeeping.com/issues/2004-09/rhf/index.php

[DarthFred6996]

It very well could be your test. The strip test that can be used for fresh or salt is really no good. My ph using the strip test showed 7.8 for my salt tank as well, but my alkalinity was ideal. A better test at my LFS showed that my ph was actually 8.2. The strip test I had had readings for 7.8 and 8.4 and nothing in between, so it was impossible to really tell what the ph was. Buy a better test or take a sample to the LFS to check. You will probably find out that you are in better shape than you think.

[5xevy]

It very well could be your test.

That's true too. I just bought a pH monitor recently and it's much more accurate than those liquid tests, down to the hundredth (.01).

[salty420]

Increased CO2 levels can result in a low pH.
Do you have a good water flow on the surface ie a powerhead near the surface? What's your turnover rate?

The tank is 37 gallons, I have 2 powerheads totaling 570 gph and it's got an eclipse top which is running so that's adding some flow as well.

I've tested the pH with the dip stick and the aquarium pharmaceuticals drop test so I think it's gotta be pretty darn close to the 7.8 reading. I've had no luck with buffers in my FW tank, think they'd work on the SW?

The tanks been running for, hmm, 3 weeks? So hopefully it will go up after the cycle is complete.

Any ideas on why the pH is so much lower in the SW tank then the FW tank? How is it dropping from the level out of the tap?