PH Problems

[RichardScottRice]

I don't know whatever possessed me to setup a nano tank, but I did. And it has been a total frustration from day one. Mostly battling PH issues. I'm not new to reef tanks, but all my tanks in the past have been upwards of 100 gal. This 24gal tank is driving me nuts with the PH swings. I will do a water change and add some PH Boost and get it up to about 8.1 - which is still low and within 24 hours its back down to about 7.8 - sometimes even lower at night. I'm trying to avoid setting up a CA reactor or dripping Kalk for such a small tank, but I may not have any choice.

It has been setup for 3 months now. Ammonia and nitrites are zero. Nitrates are between 3 and 5, dKH is high, about 9. CA is also high at about 480. SG is 1.025. All that is in the tank right now is a cleanup crew as I didn't want to subject anything else to the fluctuations. I did have an algae bloom that has been over for about a month now. Skimmer is running find and pulls about 2-3 ounces of thick dark green goo out every day. Other than that the tank seems fine. In spite of the low PH I haven't lost any inhabitants

Any Thoughts? HELP!!!!

[kevin2000]

So long as you have reasonable alkalinity and aeration PH controls itself. Its common for PH to swing anywhere from 7.8 - 8.5. Don't try and manage Ph by dumping additives into the tank .. gauranteed to give you problems.

[papagimp]

I've had a 55g running a PH of 7.8 for about 2 years now. My newer 75g runs al ittle closer to 8.0. I think once upon a time a year or so ago, I saw my PH hit 8.3. Only the once though. I don't even worry about it anymore, especially since all the other parameters stay good.

[old salty]

Always treat pH reading apparatus with suspicion; this includes $1500 pH meters if you have them. What are you measuring the pH with and have you verified the measurements?

Once you have verified that the measurements are correct, the next item I would check is your salt. Mix up a batch of water to 1.026 and check the pH in 24 hours. It should read 8.3 or pretty close to this.

If you are using an additive to increase pH, and 8.1 is the highest the pH goes, the additive is not working as it should. The idea that the pH is falling back down to 7.8 makes me think that whatever additive you are using is "junk" in a bottle.


Again, it is important to verify your pH numbers before you do anything.

[kevin2000]

PH is probably the most misunderstood basic chemistry item facing an aquarist. The concept that there is a magic number that each aquarium must have seems to be a common perception and is dead wrong.

PH naturally fluctuates in all aquariums in large part to the process to photosynthesis where the micro algae which abound in the aquarium consume CO2 (which would otherwise depress PH) during the daylight .. and then expel CO2 during the nighttime. Common for tanks to have PH of 7.8 -8.5 depending on how long the lights have been on/off.

For the most part PH handles itself in our aquariums ... the two prerequisites are a reasonable level of alkalinity (aka buffer) and some aeration (surface water turbulence normally suffices). With adequate air exchange the buffers withing the waters will manage CO2 levels and keep PH within a reasonable range.