Running my pH at 8.7 - 8.9. What are your experiences with super high pH?

[smartwater101]

This is not necessarily an "issue", its more a curiosity about other peoples experiences.

(I'm in the process of upgrading to GHL, so these readings are coming from both Apex and Profilux. Probes recently calibrated)

So when I switch to @Randy Holmes-Farley's recipe #2 (1.5x concentration), I finally got my pH up where I wanted it around 8.45 - 8.55. Its a 160 mixed reef with lots of frags, but nothing too large. My alkalinity consumption, as you would imagine, is pretty high. But with good growth (which was the goal) and everything seems fine. I normally keep the Alk ~9.4 - 9.5. My frag tank lights, fuge lights, skimmer, and dosing schedule are all programmed to balance out the pH fluctuations and keep Alkalinity stable throughout the day and night.

I've never seen much info from people who run 8.6 and above, so I did my best to keep it below that. And for a few months, 8.53 - 8.6 was where the pH stayed. (with Alk continuing ~9.5)

Here is where running such high pH can be a bit of a headache. As I'm trading out GHL/Apex I forget to dose for 2 days. And I traded out the Alkatronic for a reefbot (a HUGE mistake, sigh) So normally 2 days is not a huge deal, but with pH sooo high, the Alk consumption rate is also high. And with my testing becoming inconsistent (ultimately my bad) the Alk dropped. But the pH didn't fluctuate to much (down to 8.5)

Now that I'm back on a normal dose/test schedual. Alk is back up to 9.0 and pH is 8.7 - 8.9!

Corals have had zero side effect from any of this. Unfortunately my fav thing in the tank (long tentacle anemone) is furious. He looks terrible. I'll of course be doing some water changes over the next few days since running pH @ 8.7 for a week seems to be where the downside starts for my tank. Also running with no lights for the next day or so.

AAAAAAnywaaaayy, I guess I just wanted to share my experience so far and, since there isn't a lot of threads talking about this high of pH. I wanted to get some takes from you peeps. Any thoughts or long-term experiences in the 8.6+ range?

 

[Iván Olalla]

Have ran my pico reef in the 8.5/8.6 range using kalk, good growht on sps, just keep in mind that ammonia toxicity skyrocket with elevated ph

 

[GainesvilleReef]

Are you seeing lots of precipitation? Also, how old is your probe? They do creep upwardly with age.

 

[smartwater101]

GHL probe is less than a month and BRS probe is ~2 months. Recalibrated about a week ago.

I double checked last night and it looks like they're both reading ~1.1 higher than I originally said.

 

[smartwater101]

As for precipitation, I get a small amount of buildup along the wall where it's dosed. But doesn't seem to be anything crazy. I'll pull the return pump this weekend and give it a look/cleaning.

 

[BeejReef]

following. When very young, my tank ran at 8.5+
never could find anything on running high either.

Gorgeous tank! Really only 160g? Your tank makes the hippo tang look like a flame angel.

 

[Halal Hotdog]

Have ran my pico reef in the 8.5/8.6 range using kalk, good growht on sps, just keep in mind that ammonia toxicity skyrocket with elevated ph

Could you elaborate on the ammonia toxicity at elevated pH?

 

[smartwater101]

following. When very young, my tank ran at 8.5+
never could find anything on running high either.

Gorgeous tank! Really only 160g? Your tank makes the hippo tang look like a flame angel.

Thanks! Yeah I like a long tank and LOTS of smaller fish. The Hippo and Foxface are the only larger dudes. Might seem empty at first glance but I have a ton of nano fish filling it out. Even have 25 masked gobies. Its fun to look for all the little creatures. Plenty of activity no matter where ya look.

 

[Iván Olalla]

Could you elaborate on the ammonia toxicity at elevated pH?

Not native speaker here, but i´ll try: total ammonia nitrogen is what our test kits measure in the tank, it works in a two side scale: positive and negative charged ions, the balance is held by the ph (likely like mg keeps ca and kh in check for example, but here is ammonia and ammonium)

While ammonium is not toxic for the fish per se, ammonia is. The higher the ph, the more ammonia is present in the total ammonia nitrogen measurement. In low ph nitryfing bacteria have a hard time proccesing ammonia into nitrites and it´s population doesn´t thrive that well, in the other range; elevated ph while good to the bacteria in upper scales can lead to more ammonia than ammonium present in the system which is toxic for our fishes

eg. in an established system with a temperature of 28° C, a pH of 7.0, and a total ammonia nitrogen of 5 ppm has only .03 ppm ammonia while in water with a pH of 9.0, that has a total ammonia nitrogen of 5 ppm your ammonia level is 2.06 ppm which is toxic for the fish


Hope that helps, regards!

 

[Halal Hotdog]

Very interesting, definitely something to keep in mind. I imagine the key would be to go slow, so the bacteria are able to convert it through the nitrogen cycle.

 

[Iván Olalla]

Very interesting, definitely something to keep in mind. I imagine the key would be to go slow, so the bacteria are able to convert it through the nitrogen cycle.

Could be, depending of the culture strains you've un, sometimes we develop monocultures that are very specific in their environment needs and could struggle in an elevated pH. I submitted and article here in that regard but has not been reviewed yet, i can copy and paste it to you in pm if you like!

 

[Wrasse-cal]

Bumping this older thread. Anyone else have experiences with higher pH?