pH ..too high?

ptreef · 11/27/2018, 08:50 AM

So tank is established well over 5 yrs.
SPS dominate with some lps and zoas. My pH is steady and consistent with a low of 8.4 in the am and then 8.7 in the late eve after lights out. Which seems a bit on the high side. This is normal for all seasons.

Overall colors and corals and fish look and are doing fine. Growth seems slow but only basing on what others seem to have.
Alk is 8.0 Aim for 8.5 and check or adjust every 1-2 weeks
Cal is 450 aim for 450
Mg is 1500 aim for 1350 and check and adjust monthly
PPT is 35/1.026
Top off is RO/DI

Tank is in the basement with decent air flow and circulation. I dose 2 part with soda ash (alk) and calcium.

Anything to fuss over or to do to lower a few tenths or just leave it be.

lpsouth1978 · 11/27/2018, 09:24 AM

It does seem a bit high, but not CRAZY high. The Soda Ash is the likely culprit. Soda ash has a raising effect on pH. You could try replacing some of the soda ash with baking soda to balance things out at a lower pH, while still maintaining Alk.

ptreef · 11/27/2018, 09:57 AM

Im dosing 210ml of soda ash/day, so going to baking soda i'd need to dose 420ml (based on normal mixing...
Will that help much do you thing on 350g water volume?
Also I dose currently every 2 hrs. So about 17-18ml every 2 hrs

i guess if i could get it on average down maybe .2 that would help

lpsouth1978 · 11/27/2018, 10:09 AM

I definitely think it will help. Soda Ash raises pH significantly, so I would start with half soda ash - half baking soda and see where you end up after a few days. Adjust the ratio a bit more, wait, test, adjust, etc, until you have the pH in the range you want (8.0-8.3ish).

ptreef · 11/27/2018, 10:13 AM

Sounds good....Thanks,

Can one make the Baking soda mix more concentrated to have to dose less daily?
ie...
normal instruction mixing is 1cup & 2 tablespoons/gal of water...and i'd be around that 420ml/day.
instead go to like 2 cups / gal of water and then be back to 210ml/day?
Obviously watch my levels close till i get dosing amounts dialed in....

But will it not mix up and store correctly more concentrated

Uncle99 · 11/27/2018, 10:32 AM

i might firstly test the PH number your getting to ensure it is absolutely accurate, then if it is, yes, I would lower it a couple of points.

8.7 seems high with an Alk of 8.0, I would have thought Alk must be in the 11 range to get a PH that high..

A PH on the higher side of the range is not a bad thing, many people struggle with 7.8.

nereefpat · 11/27/2018, 10:46 AM

Have you calibrated the pH probe lately?

In general, unless you are seeing precipitation, then I wouldn't worry about high pH.

ptreef · 11/27/2018, 11:48 AM

I haven't calibrated recently, but do have the solution and will check before making a change

Scrubber_steve · 11/27/2018, 05:51 PM

Quote:

Originally Posted by ptreef

I haven't calibrated recently, but do have the solution and will check before making a change

maybe your calibration solution also needs calibration check ?

bertoni · 11/27/2018, 10:07 PM

I don't particularly believe the 8.7 reading for pH. That's fairly high, although a large soda ash (sodium carbonate) dose might do that. You could try baking soda. Unfortunately, it's a lot less soluble, so it can only be made about half as concentrated. I'd probably double-check the pH measurement before spending much time or effort on this, though.

ptreef · 11/28/2018, 12:04 PM

Cleaned the probes last night and will calibrate tonight and see.
Hopefully the probe has just drifted as you guys suspect.

I went back in the apex log and it has been reading 8.4 morning to 8.7 night very consistent the last 3 mos

ptreef · 11/29/2018, 07:53 PM

Got it all calibrated. Looks like it was off about .35
I'm at 8.35 in Eve. I'll see how it looks in am, but probably be like 8.0's.
And also see how it patterns out. But looks to be perfect then!
Thanks all for the input and help.

five.five-six · 11/29/2018, 09:20 PM

Quote:

Originally Posted by ptreef

I haven't calibrated recently, but do have the solution and will check before making a change

Spend the 6 bucks and buy individual 7 and 10 packets. If you have a bottle of calibration solution and you leave it open, Co2 in the air will contaminate it and loser it's pH. also be mindful of the temp chart printed on the packet.

also, as your tank matures, there will be more and more Co2 consumption and your pH can naturally rise.

five.five-six · 11/29/2018, 09:29 PM

Quote:

Originally Posted by ptreef

Cleaned the probes last night and will calibrate tonight and see.
Hopefully the probe has just drifted as you guys suspect.

I went back in the apex log and it has been reading 8.4 morning to 8.7 night very consistent the last 3 mos

Look at the probes, there should be a liquid in the probe. when that liquid runs out, you can either refill it or replace it.

11/27/2018, 08:50 AM	#1
ptreef Registered Member Join Date: Nov 2012 Posts: 746	pH ..too high? So tank is established well over 5 yrs. SPS dominate with some lps and zoas. My pH is steady and consistent with a low of 8.4 in the am and then 8.7 in the late eve after lights out. Which seems a bit on the high side. This is normal for all seasons. Overall colors and corals and fish look and are doing fine. Growth seems slow but only basing on what others seem to have. Alk is 8.0 Aim for 8.5 and check or adjust every 1-2 weeks Cal is 450 aim for 450 Mg is 1500 aim for 1350 and check and adjust monthly PPT is 35/1.026 Top off is RO/DI Tank is in the basement with decent air flow and circulation. I dose 2 part with soda ash (alk) and calcium. Anything to fuss over or to do to lower a few tenths or just leave it be.

11/27/2018, 09:24 AM	#2
lpsouth1978 Registered Member Join Date: Jan 2007 Location: Arizona Posts: 915	It does seem a bit high, but not CRAZY high. The Soda Ash is the likely culprit. Soda ash has a raising effect on pH. You could try replacing some of the soda ash with baking soda to balance things out at a lower pH, while still maintaining Alk. __________________ Current tank: 40B work in progress w/20L sump

11/27/2018, 10:09 AM	#4
lpsouth1978 Registered Member Join Date: Jan 2007 Location: Arizona Posts: 915	I definitely think it will help. Soda Ash raises pH significantly, so I would start with half soda ash - half baking soda and see where you end up after a few days. Adjust the ratio a bit more, wait, test, adjust, etc, until you have the pH in the range you want (8.0-8.3ish). __________________ Current tank: 40B work in progress w/20L sump

11/27/2018, 10:46 AM	#7
nereefpat Registered Member Join Date: Apr 2016 Location: Central Nebraska Posts: 3,190	Have you calibrated the pH probe lately? In general, unless you are seeing precipitation, then I wouldn't worry about high pH. __________________ Pat Current Tank Info: 125 in-wall , 40b sump. 6 bulb T5. ASM G2 skimmer. LPS and leathers

11/27/2018, 10:07 PM	#10
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	I don't particularly believe the 8.7 reading for pH. That's fairly high, although a large soda ash (sodium carbonate) dose might do that. You could try baking soda. Unfortunately, it's a lot less soluble, so it can only be made about half as concentrated. I'd probably double-check the pH measurement before spending much time or effort on this, though. __________________ Jonathan Bertoni

11/27/2018, 09:57 AM	#3
ptreef Registered Member Join Date: Nov 2012 Posts: 746	Im dosing 210ml of soda ash/day, so going to baking soda i'd need to dose 420ml (based on normal mixing... Will that help much do you thing on 350g water volume? Also I dose currently every 2 hrs. So about 17-18ml every 2 hrs i guess if i could get it on average down maybe .2 that would help

11/27/2018, 10:13 AM	#5
ptreef Registered Member Join Date: Nov 2012 Posts: 746	Sounds good....Thanks, Can one make the Baking soda mix more concentrated to have to dose less daily? ie... normal instruction mixing is 1cup & 2 tablespoons/gal of water...and i'd be around that 420ml/day. instead go to like 2 cups / gal of water and then be back to 210ml/day? Obviously watch my levels close till i get dosing amounts dialed in.... But will it not mix up and store correctly more concentrated

11/27/2018, 10:32 AM	#6
Uncle99 Crab Free Zone Join Date: Sep 2017 Location: Ontario, Canada Posts: 2,906	i might firstly test the PH number your getting to ensure it is absolutely accurate, then if it is, yes, I would lower it a couple of points. 8.7 seems high with an Alk of 8.0, I would have thought Alk must be in the 11 range to get a PH that high.. A PH on the higher side of the range is not a bad thing, many people struggle with 7.8.

11/27/2018, 11:48 AM	#8
ptreef Registered Member Join Date: Nov 2012 Posts: 746	I haven't calibrated recently, but do have the solution and will check before making a change

11/28/2018, 12:04 PM	#11
ptreef Registered Member Join Date: Nov 2012 Posts: 746	Cleaned the probes last night and will calibrate tonight and see. Hopefully the probe has just drifted as you guys suspect. I went back in the apex log and it has been reading 8.4 morning to 8.7 night very consistent the last 3 mos

11/29/2018, 07:53 PM	#12
ptreef Registered Member Join Date: Nov 2012 Posts: 746	Got it all calibrated. Looks like it was off about .35 I'm at 8.35 in Eve. I'll see how it looks in am, but probably be like 8.0's. And also see how it patterns out. But looks to be perfect then! Thanks all for the input and help.