Annoying Alk & pH issue

[Boomer]

Nick

While I was there, the owner also "forced" me to borrow a Milwaukee mw600 dissolved oxygen meter.

In main display, DO is showing at 8.3 mg/l.
In sump DO Is showing at 7.9.
In 58 display, DO is showing at 8.1

CAN'T HAPPEN First, it can not adjust for barometric pressure or seaward salinity. Seawater at 100 % saturation is 6.6 ppm at sea level, that 8.3 ppm is 126 % saturated. 95 % of all reef tanks do not even make 100%, thus are lower than 6.6 ppm.

Mojo, I looked up soda lime.

You have not seen the countless threads on CO2 Scrubbers on fourms. Soda lime is granular Kalk, Ca(OH)2 Ca(OH)2 + CO2 ---> CaCO3 + H2O, Calcite or Aragonite. thefilterguys sells all the stuff needed to make one. There is also the liquid CO2 scubber.

1. Get a container with a screw on tight lid.
2. Drill a hole in the side near the bottom to fit a air-line tube nipple.
3. Drill a hole of the same in the container top lid
4. Fill container 2/3 full with RO/DI water
5. Add powder or granular sodium hydroxide till all dissolves and it reaches saturation.
6. Attach input air-line to bottom-side
7. Attach output air-lien to tip lid outlet.

As air enters the bottom-side the air bubbles up through the NaOH. NaOH + CO2---> NaHCO3 ( baking soda). The CO2 free air enters under the lid which is a 1/3 air-gap. This gets pressurized and the free CO2 air is pumped out through the lid outlet to the skimmer. You need an air-pump for this one.

No matter what has happened or changed in this tank you have a CO2 issue....PERIOD


According Joe,(the owner), 10.0 is ideal= A Knothead.

Even FW at 100 % sat is only 8.3 ppm

Please send Joe here for chem lessons


Lesson # 1

DO in aqueous waters

Why O2 is important in water
http://www.lenntech.com/why_the_oxygen_dissolved_is_important.htm


Dissolved Oxygen

Oxygen Solubility in Fresh and Sea Water


Oxygen Saturation Calculation Based on Temperature and Elevation


The Need to Breathe, Part 3: Real Tanks and Real Importance by Eric Borneman - Reefkeeping.com

Getting deeper


Ambient Water Quality Criteria for Dissolved Oxygen

How can I predict oxygen solubility in water?
Thermidaire D.O Calculater Oxygen solubility water treatment chemicals

My complex formula

S1= S x P / 29.92 - ( C X F)

S1= Solubility for Corrected Pressure

P= Barometric Pressure (Barometer reading in inches)

S = Solubility of Distilled Water (from table, 8.2@25C & 7.9@28C)

C = Chlorinity Reading of Sample (for us 18-20 ppt Chlorinity, std
seawater is 19=35 ppt Salinity or Chlorinity = Salinity / 1.842). For mS , mS / 2.789 = Chlorinity.

F = Chlorinity Factor, from table (for us it will always be .08)

If your tank is 82 F that will be about 6.4 ppm =100% Saturation


pH showing 7.77
Dkh showing 11.2 (same Salifert kit as above)
Salinity is 1.024
Temp is 90 degrees F in mixing barrel,

pH should be 8.7

 

[Maxx]

just went looking for new mixed numbers.. your ph is down on fresh mixed? how long you had this bucket of salt? could it be the problem?
Do you add your salt to 90 degree ro/di? that will affect how it mixes, colder the better for initial adding of salt

Sasquatch,

First of all, your avatar is creeping RTF out....The idea of Isopods eating cheeto's is just wrong.

Salt was a new mix from a 50 gallon bag, from a 200 gallon box., (Four 50 gallon bags of salt). RO/Di is kept in a 44 gallon Brute trash can with an air tight lid. I know its air tight because when I topped off the sump with a couple of gallons 2 days ago, the pH rose for a bit.

The RO is pumped into a 55 gallon blue plastic barrel with a hole cut in the top, and thin sheet of lexan attached to the top via nylon screw to keep stuff from falling into my salt mix. When the barrel is full, salt mix is added, and the Mag 9.5 is turned on. Mag 9.5 used to stay on until I drained the majority of the water from it, and it began sucking air. But then I realized it was running at 90F so that has since changed for the warmer months.

The pH of the freshly made salt mix is low due to the barrel not being air tight. Hope that makes sense.

Nick

 

[Maxx]

Boomer, its too bad you're getting all soft and cuddly in your old age. I can remember when you would have made some pithy sarchastic reply regarding the misinformation I was given.

Regardless, I appreciate the info and will do my best to send Joe here for Chem lessons. I'll be sure to tell him how gentle and patient you are with knotheads.



Regarding the CO2 scrubber, I'm guessing the Soda lime cannot be recharged? Once my pH begins to climb again, I know that its time to clean and refill my homemade scrubber?

For my scenario, should I run the dry CO2 scrubber on the intake of the skimmer, and then the liquid scrubber on the air pump running from upstairs? Or will one or the other of these be enough to up the pH of my system?

Thanks again for all the info Boomer and Mojo!

Nick

Nick

While I was there, the owner also "forced" me to borrow a Milwaukee mw600 dissolved oxygen meter.

In main display, DO is showing at 8.3 mg/l.
In sump DO Is showing at 7.9.
In 58 display, DO is showing at 8.1

CAN'T HAPPEN First, it can not adjust for barometric pressure or seaward salinity. Seawater at 100 % saturation is 6.6 ppm at sea level, that 8.3 ppm is 126 % saturated. 95 % of all reef tanks do not even make 100%, thus are lower than 6.6 ppm.

Mojo, I looked up soda lime.

You have not seen the countless threads on CO2 Scrubbers on fourms. Soda lime is granular Kalk, Ca(OH)2 Ca(OH)2 + CO2 ---> CaCO3 + H2O, Calcite or Aragonite. thefilterguys sells all the stuff needed to make one. There is also the liquid CO2 scubber.

1. Get a container with a screw on tight lid.
2. Drill a hole in the side near the bottom to fit a air-line tube nipple.
3. Drill a hole of the same in the container top lid
4. Fill container 2/3 full with RO/DI water
5. Add powder or granular sodium hydroxide till all dissolves and it reaches saturation.
6. Attach input air-line to bottom-side
7. Attach output air-lien to tip lid outlet.

As air enters the bottom-side the air bubbles up through the NaOH. NaOH + CO2---> NaHCO3 ( baking soda). The CO2 free air enters under the lid which is a 1/3 air-gap. This gets pressurized and the free CO2 air is pumped out through the lid outlet to the skimmer. You need an air-pump for this one.

No matter what has happened or changed in this tank you have a CO2 issue....PERIOD


According Joe,(the owner), 10.0 is ideal= A Knothead.

Even FW at 100 % sat is only 8.3 ppm

Please send Joe here for chem lessons


Lesson # 1

DO in aqueous waters

Why O2 is important in water
Why is important the oxygen dissolved in water


Dissolved Oxygen

Oxygen Solubility in Fresh and Sea Water


Oxygen Saturation Calculation Based on Temperature and Elevation


The Need to Breathe, Part 3: Real Tanks and Real Importance by Eric Borneman - Reefkeeping.com

Getting deeper


Ambient Water Quality Criteria for Dissolved Oxygen

How can I predict oxygen solubility in water?
Thermidaire D.O Calculater Oxygen solubility water treatment chemicals

My complex formula

S1= S x P / 29.92 - ( C X F)

S1= Solubility for Corrected Pressure

P= Barometric Pressure (Barometer reading in inches)

S = Solubility of Distilled Water (from table, 8.2@25C & 7.9@28C)

C = Chlorinity Reading of Sample (for us 18-20 ppt Chlorinity, std
seawater is 19=35 ppt Salinity or Chlorinity = Salinity / 1.842). For mS , mS / 2.789 = Chlorinity.

F = Chlorinity Factor, from table (for us it will always be .08)

If your tank is 82 F that will be about 6.4 ppm =100% Saturation


pH showing 7.77
Dkh showing 11.2 (same Salifert kit as above)
Salinity is 1.024
Temp is 90 degrees F in mixing barrel,

pH should be 8.7

 

[Sasquatch]

Sasquatch,

First of all, your avatar is creeping RTF out....The idea of Isopods eating cheeto's is just wrong.

Salt was a new mix from a 50 gallon bag, from a 200 gallon box., (Four 50 gallon bags of salt). RO/Di is kept in a 44 gallon Brute trash can with an air tight lid. I know its air tight because when I topped off the sump with a couple of gallons 2 days ago, the pH rose for a bit.

The RO is pumped into a 55 gallon blue plastic barrel with a hole cut in the top, and thin sheet of lexan attached to the top via nylon screw to keep stuff from falling into my salt mix. When the barrel is full, salt mix is added, and the Mag 9.5 is turned on. Mag 9.5 used to stay on until I drained the majority of the water from it, and it began sucking air. But then I realized it was running at 90F so that has since changed for the warmer months.

The pH of the freshly made salt mix is low due to the barrel not being air tight. Hope that makes sense.

Nick

creepy? haha. umm this is a bit too deep a subject for me on the new mix but I was of the understanding that if new mix dosen't get aerated the C02 in the mix won't be driven off and it won't mix up right? could you add a bubbler to it?

 

[Maxx]

I could, but I need to address the tank pH issue first.

I went ahead and ordered a new pH probe from Premium Aquatics, and all the stuff for the co2 scrubber from the filter guys. For some reason they have it listed as "Skimmer Media" instead of co2 scrubber...

Hopefully that makes a difference.

Thanks guys.

Nick

 

[Boomer]

Nick

Regarding the CO2 scrubber, I'm guessing the Soda lime cannot be recharged?

No, not unless you know how to convert cement back to Kalk that is cheap




For my scenario, should I run the dry CO2 scrubber on the intake of the skimmer, and then the liquid scrubber on the air pump running from upstairs? Or will one or the other of these be enough to up the pH of my system?

If the incoming skimmer air is is not coming form the air pump run both.



Hopefully that makes a difference....Skimmer Media" instead of co2 scrubber...

It is the same. Just using different words at the filterguys.

 

[Maxx]

New pH probes arrived today. Immediately calibrated it and stuck it in the tank.

Old probe,(recently recalibrated), showed 7.84
New probe showed 7.95 right away, and rose to 7.99 within an hour.

I'm on midnights right now and will be home by 7 am. I can see what the pH dropped down to then, but I'm already much happier about things. Still low, but not as bad.

Current "fixes"

Macro in sump lit 24/7
Powerhead in Macro section turned off
Skimmer intake drawing outside air
Airpump pushing air from upstairs down to air stone in sump

Ca Rx has been running for about 4 days now. Dkh has been 9.9 for two days running.

The CO2 scrubber is in bound and will be run to the skimmer intake first. Hopefully, between all of these things, I can bump the pH up to 8.0 at night and 8.1 ish during the day.

Thanks again for all the info, suggestions, and help guys.

Nick

 

[Boomer]

OK, looks like the probe. The CO2 scrubber should get you in the low 8's

 

[Maxx]

Current parameters:

Dkh- 9.9
Ca - 385
Mg - 1350
pH - 8.19
Salinity - 1.027 via refractometer
Temp 80f

Co2 scrubber installed 9-1-11
Mg supplement added 9-2-11, (BRS mg 2 part 10 Tbsp mg sulfate 6 Tbsp mg chloride...might have chloride&sulfate switched...I'm upstairs, its downstairs...dosed at 5/3 ratio as per directions)
Total of 3 Derasa clams, and 2 maxima clams added to system since 8-22-11
Cheato and some Ulva added to sump with 24/7 lighting cycle
Airstone added to sump pumped in from upstairs via petco air pump
New pH monitor calibrated & added to system on 9-1-11

This morning at 6 am pH read 7.99 with only sump lit for macro.

I think my skimmer being undersized for my current water volume and being a recirc design that sucks less air than current models maybe contributing to the slow pace of pH rising. But I'm actually okay with that as it's probably easier on my critters to have it raise slowly over several days.

Dkh reading has been constant at 9.9 since 9-1-11.

Thanks guys, I really appreciate all of the help and information.

Nick

 

[mojoreef]

Hey Maxx I didnt ask before but is your monitor temp compensated??

Mojo

 

[Maxx]

No idea,(meaning probably not). Its a Pinpoint pH monitor. Why? How off is it from what it should be at that temp?

This morning at 715 am, pH was reading 8.03. No lights on except fuge/sump light.

Nick

 

[Maxx]

Update 10-01-2011

PH has been running about 8.02 during the day, and dropping to about 7.9 - 7.85 during the night.

Changes made to the system thus far:

Old H&S Re-Circ skimmer has been replaced with a used Octopus Xtreme 250 powered by 2 Sicce PSK 2500 pumps. I was told the skimmer came with PSK 1000 pumps which are less problematic than the 2500's but that's another story. Suffice it to say the 2500's will be replaced by a single Bubble Blaster 5000 pump when the adapter kit comes. The new skimmer pulls 4 times the air of the old skimmer and the pumps are being fed both outside air and room air pulled through the Co2 scrubber I bought from the filter guys. When the adaptor kit arrives, the bubble blaster will pull outside air through the Co2 scrubber and it will pull 50% more air than the skimmer currently does. The idea being more low Co2 air being introduced to the tank.

I also replaced the old craptastic Pinpoint pH monitor and replaced it with a Reef Fanatic pH Controller. If nothing else, the RF unit is ridiculously easy to calibrate compared the Pinpoint.

I've moved my chaeto to the frag tank and its on a reverse lighting cycle from the main display, and to be honest, I really dislike that. It sucks up room in the frag tank and looks like hell. I moved it out of the sump because the sump is a natural settling point for detritus in my system and I prefer to siphon it out without having to stop and clear out blockages caused by loose chaeto etc. The chaeto also trapped alot of that debris in itself and made a bigger mess.

So here are two potential additional changes to the system:

Debating getting a couple of CPR HOB aquafuges to move the Chaeto to. Not expecting much (if any) improvement to the pH using those things, they just get the chaeto out of my frag tank, and wont hurt the pH levels at all.

With that comes getting a Kalk reactor and having it run only at night to boost pH over 8.

My concerns with the Kalk reactor are how it will affect my other parameters. Current parameters as of last evening:

Temp 80F
Salinity 1.026
Dkh - 9.3 as per new Salifert kit, (old one was about a year old)
Ca - 410 as per new Salifert kit
Mg - 1470 as per new Salifert kit

I dont want the Dkh to rise very much if I can help it, but I dont know how realistic that is with a Kalk doser. I like where my parameters are at right now for the most part, and my corals are showing good growth. Its just the damn pH that's annoying me...

Boomer, is there a way to minimize the alk boost of Kalk without affecting the pH boost? I'm thinking not, but it never hurts to ask.

Thoughts/comments/suggestions?

Thanks,

Nick

 

[Guerry]

IMO there's alot more things going on to effect ph than just adding air from every source we can find and as for just raising alk to get higher levels thats short term gain. I had same problem and tried every thing and more it would go anywhere from 7.6 to 8.0 for over a year. I finally just threw my hands up and stopped chasing my tail, funny thing is now two years later I matain Dk at 7.8 and my ph is always between 8.2 and 8.4

 

[Maxx]

I'm trying to NOT raise my alkalinity from its current levels of 9.3-9.6 but want to raise my pH of system which is in the basement, to reliably above 8 with as little deviation as possible between lights on and lights off.

I'd be willing to settle for a consistant 7.95 if it wouldnt swing too much throughout the light cycle.

Nick

 

[Boomer]

Nick

Boomer, is there a way to minimize the alk boost of Kalk without affecting the pH boost? I'm thinking not, but it never hurts to ask.

You should get little Alk boost with Kalk, it is mostly a pH boost, as the Kalk sucks up CO2. Are you adding any other kind of Alk sup ?

 

[Maxx]

No, no alk supplements at all. Just Ca reactor and water changes.

What are your thoughts on a "De-Gassing Tower" as per Bill Wann's 20,000 Gallon Tank Construction thread, (pg 15)

The tube on the right side is the degassing tower . it is 6 inch diameter and 3 feet tall filled with bio balls . water from the reactor enters the top of the tube and flows over the bio balls . the degassed water leaves the degassing tower at the bottom red tube . air is blown into the bottom of the tube and flows out the top through a side port . so far this simple design is working great . I have the materials for the big one and will post info when I start building it . If anyone needs a drawing let me know and I will post one . the new one will be 8 inch diameter by ten feet tall .

Not sure how this wouldnt become a giant nitrate factory...granted his is on a 20K gallon system, but still...


Thanks again Boomer for all the help.

Nick

 

[Boomer]

Degassing towers are common place in large aquariums but there use is really not a CO2 thing but revolves around un-Brominated salt mix using Ozone or N2 gas accumulation. DT vent all air outside.

If that pic is claimed to be a degassing tower, well it really is not. It is nothing more than a trickle filter. And DT have massive air flow in them.

 

[Maxx]

Degassing towers are common place in large aquariums but there use is really not a CO2 thing but revolves around un-Brominated salt mix using Ozone or N2 gas accumulation. DT vent all air outside.

If that pic is claimed to be a degassing tower, well it really is not. It is nothing more than a trickle filter. And DT have massive air flow in them.

So a couple of old Pringle's cans duct taped together, stuffed with a fistfull of bioballs and and old airpump arent going to magically boost my pH to 8.2 and keep it steady???? That bites....


All kidding aside....I'm leaning towards adding a Kalk stirrer to the mix and using it to slowly increase my pH to about 8.1-8.2 ish and leave it at that. I've actually got an extra Liter Meter dosing pump so I can use it to dose the Kalk.

Just out of curiousity, what do you guys feel is an acceptable swing in pH between light/dark cycles for SPS? Obviously less of a swing is better, but is a drop from 8.2 down to 8.1 okay, or do you want it to be less than that for optimal growth?

Nick

 

[Sasquatch]

Maxx, just a silly thought? have you tried using the two displays on opposing light schedules?

 

[NC2WA]

Nick,

I would think a drop of 0.1-0.2(max) would be acceptable.