PH

[davidwillis]

I don't understand why my PH won't go over 8.0. I dose soda ash for my alk, but it won't take ph over 8.0. when I start dosing, it quickly goes up, but then hits a plateau. I dose vinegar during the day, which pulls it down to 7.8-7.9, then soda ash brings it back up to 8.9 during the night. I guess this ph range is not bad, and who knows if my probe is even correct (I checked with an api ph test, and it also showed 8, but again I don't trust it much). But mainly I am curious as to why soda ash, and connecting an outside line to my skimmer does not raise ph over 8.

But is what I am wondering is why does it not keep climbing with adding soda ash? If you look at yesterday vs today, I dosed 2X soda ash today vs yesterday, but the ph loos almost identical.

I also tried running a line outside for my protein skimmer, and let it run for 3 days, with no change to PH. I did that a few months ago, so the chart I attached does not show that time frame.

specs:
300 gallong tank
alk 7.84 (went up to 8.1 after dosing extra soda ash)
ca 430
mg 1464
PH: 7.8-8.0

 

[jda]

It is almost certianly high co2 levels in the home. Nothing can overcome this for long - kalk and other high pH additives are only temporary.

I would triple check any pH meter or probe before you chase this too much. Those values all appear in range, but the probes are the least reliable piece of equipment in any tank, IME.

 

[KrisReef]

I have a calcium reactor and until I got it running properly it kept my pH low, in the 7’s.

I think the constant change over the day is probably more harmful to the environment than the low number that it is tending towards.

You need to identify the source of the problem in order to get a solution that will be stable ( in a smaller range) for best performance of your coral, imo.

I would suggest checking out all the possible sources for pH measurement errors and pH movements and changing these things one at a time and then you can address the root causes, rather than worrying about the pH value detected by a probe that may not be accurate or reliable?

I think this is why you have posted so I apologize if I am not clear? Go slowly and keep it stable first, your situation may not allow pH 8.4, but trying to continuously bump it into submission is an impossible task for most people.

 

[jda]

I have a calcium reactor that melts 22kg of media every 6-9 months and my pH is in the high 8.1 to 8.3 range. The co2 in my home rarely gets above 500, through. My CaRx is tuned well with no undissolved co2 escaping into the tank - this can be huge.

IMO, the first step is to get a co2 reading in the room.

 

[davidwillis]

It is almost certianly high co2 levels in the home. Nothing can overcome this for long - kalk and other high pH additives are only temporary.

I would triple check any pH meter or probe before you chase this too much. Those values all appear in range, but the probes are the least reliable piece of equipment in any tank, IME.

wouldn't running a line to the outside for the skimmer do something if it was the co2 level in the home?

I used a co2 meter to read the in home co2 is about 650ppm, outside is about 350ppm. So I am not sure why the line from outside to the skimmer did not help?

I don't trust the ph number much at all, but I do trust that if the ph goes up, the probe will read it going up. I am actually fine with what I have, and am mostly just curious why it would hit a plateau like it does. soda ash instantly raised the ph until it hits a level, then it won't go up, even if more soda ash is added. I just want to understand what is going on. I don't really see it as a problem, and am not trying to fix it, just curious as to why?

Is it that the soda ash is removing co2 at the same rate as co2 is being added to the tank via co2 in the air? But even then, you would think a higher dosage of soda ash would remove more, or fresh outside air to the skimmer would effect it? Or is there some other factors that I am not aware of (ph buffers, ect)?

 

[jda]

Outside line to the skimmer could help, but then you also have to factor in all of the other gas exchange. The surface and water going down the overflow is still more than air into the skimmer.

The plateau when you add the soda ash is weird - this looks like a measuring tool thing to me... just too linear.

I don't usually start to see my tank pH rise much until I get over 700ppm of co2. 800ppm of co2 can do a number. If you are at 650, then you are likely fine, but 400 would be better.

 

[davidwillis]

Outside line to the skimmer could help, but then you also have to factor in all of the other gas exchange. The surface and water going down the overflow is still more than air into the skimmer.

The plateau when you add the soda ash is weird - this looks like a measuring tool thing to me... just too linear.

I don't usually start to see my tank pH rise much until I get over 700ppm of co2. 800ppm of co2 can do a number. If you are at 650, then you are likely fine, but 400 would be better.

That is funny, I was just thinking maybe the reason why I don't see a large effect from the fresh air to the protein skimmer is due to more gas exchange through the surface. I have an open top, and good agitation. I'm not sure how to get the co2. in the house down? It is too cold to open windows, and I don't even open windows in the summer, because my wife has allergies.

 

[jda]

I live in Colorado. I just do it. If you open the windows with any kind of breeze, a minute is enough to move in a LOT of air and it doesn't even cool the place down enough for the furnace to kick on. Most people worry about the heat or cold effect on their home too much - you are just exchanging air, not cooling the place down... like a cracked window in a car for 30 seconds can exchange all of the air and nobody gets cold. Allergies are different, though...

 

[davidwillis]

ok, I opened my windows for 5 min. I did notice a temperature drop, but not bad. The co2 came down to 595. I will check it again in a few hours and see if it has gone back up.

On another note, I actually have two ph probes (I got two because I really don't trust them). I have had them for about a year, and they never read the same. Even after calibrating them, they are close for about a day, then they are off. I gave the results from my neptune systems probe, because I hope it is the more accurate one (the other one reads even lower). Even though the numbers are not the same, they both plateau and move up/down together. So I think the movement is happening, and the plateau, but I don't know the actual ph.

Is there any accurate way to measure ph to confirm? I have an api test kit, but I am not sure how much I trust it, and its precision is not very high. I tested just now.
Api = 7.8
probe1 = 7.93
probe2 = 7.77

From that I would guess the APi is close, but the only choices are 7.4 (it was obviously higher), 7.8 (looked very close), and 8.0 (was below this color). So all I know from the api test is that it is between 7.4 and 8.0.

I have other hand held ph probes, but I don't trust them as much as the apex probe.... So is there any good ph test kit that I can trust? Or does it even really matter?

 

[jda]

co2 will go back up as it mixes with the air in the rest of the house. Do this often and it goes down and stays down. When we hit a nice day, I might leave the windows open for hours, but we have other stretches when they don't get opened much at all.

 

[Troylee]

ok, I opened my windows for 5 min. I did notice a temperature drop, but not bad. The co2 came down to 595. I will check it again in a few hours and see if it has gone back up.

On another note, I actually have two ph probes (I got two because I really don't trust them). I have had them for about a year, and they never read the same. Even after calibrating them, they are close for about a day, then they are off. I gave the results from my neptune systems probe, because I hope it is the more accurate one (the other one reads even lower). Even though the numbers are not the same, they both plateau and move up/down together. So I think the movement is happening, and the plateau, but I don't know the actual ph.

Is there any accurate way to measure ph to confirm? I have an api test kit, but I am not sure how much I trust it, and its precision is not very high. I tested just now.
Api = 7.8
probe1 = 7.93
probe2 = 7.77

From that I would guess the APi is close, but the only choices are 7.4 (it was obviously higher), 7.8 (looked very close), and 8.0 (was below this color). So all I know from the api test is that it is between 7.4 and 8.0.

I have other hand held ph probes, but I don't trust them as much as the apex probe.... So is there any good ph test kit that I can trust? Or does it even really matter?

I had the same problem and chased it! My apex is way off after trying a hand held ph Meter. My apex registers 7.7-8.05 at best.. bought a new probe and calibrated it numerous times with the same outcome.. I finally bought a hand held and ph reads 8.3-8.45 on it! I have a ticket in with Neptune for this reason. I top off with kalk, leave the doors open and my skimmer pulls from outside and I couldn’t get over 8 lol

 

[davidwillis]

I had the same problem and chased it! My apex is way off after trying a hand held ph Meter. My apex registers 7.7-8.05 at best.. bought a new probe and calibrated it numerous times with the same outcome.. I finally bought a hand held and ph reads 8.3-8.45 on it! I have a ticket in with Neptune for this reason. I top off with kalk, leave the doors open and my skimmer pulls from outside and I couldn’t get over 8 lol

It seems like it is so hard in this hobby to get an accurate reading on anything. But unless both probes, and my api is off (which could be the case), I am under 8. How do you know your hand held is correct?

By the way, I remembered I have a handheld. I calibrated it, and it reads 7.9 (same as what probe 1 reads). So it would seem probe 1, and the handheld are probably fairly accurate (within the range of api, but api does not have a 7.9). But probe two is off (which is good, because it is way lower).

 

[Troylee]

It seems like it is so hard in this hobby to get an accurate reading on anything. But unless both probes, and my api is off (which could be the case), I am under 8. How do you know your hand held is correct?

By the way, I remembered I have a handheld. I calibrated it, and it reads 7.9 (same as what probe 1 reads). So it would seem probe 1, and the handheld are probably fairly accurate (within the range of api, but api does not have a 7.9). But probe two is off (which is good, because it is way lower).

I mixed fresh saltwater outside over night and got a 7.8 ph reading on my apex so I decided to buy a hand held.. I got a hand held and Calibrated it and I got a reading of 8.35… that got me chasing my apex and I tried manually calibrating it in the advanced tab and it kept failing, bought a brand new pinpoint dual probe and it read the same and wouldn’t Calibrate manually either.. I have a ticket in with Neptune and gotta make a call and share my screen with them to figure it out.. it’s just not possible to have readings that low with fresh mixed water, kalk, all my windows and doors open and skimmer pulling from outside.. I’ve had my apex drop down to 7.65 that means everything would be dead but it’s thriving! Is my hand held perfect? Prolly not but I trust it much more than my apex now.

 

[Troylee]

Post number 8 might help you! I tried it multiple times with no luck.

Apex ph probe can not calibrated

I just bought apex el from LFS and try plug everything in. However, i try to cablirate my ph probe as instruction, the problem I have is ph 10.0 fluid somehow doesn work that lead my calibration failed. Here are some pic

www.reef2reef.com

 

[davidwillis]

Post number 8 might help you! I tried it multiple times with no luck.

Apex ph probe can not calibrated

I just bought apex el from LFS and try plug everything in. However, i try to cablirate my ph probe as instruction, the problem I have is ph 10.0 fluid somehow doesn work that lead my calibration failed. Here are some pic

www.reef2reef.com

That works for me. However the probes only stay the same for less than a day. Prob #2 slowly starts dropping. Maybe it is a bad prob? I bought 2 different brands to see which is better.

 

[Troylee]

That works for me. However the probes only stay the same for less than a day. Prob #2 slowly starts dropping. Maybe it is a bad prob? I bought 2 different brands to see which is better.

I couldn’t tell ya… a good friend of mine said it’s best to build a manifold and mount them upside down with cord keepers, It keeps them from drifting is what he told me.. I’ve had it happen once a bubble got trapped in the probe and gave me whacky readings and that will prevent it.

 

[jda]

pH probes are just garbage. This sucks because they are not cheap, right? I once wrote a controller on a MacMini and I used real lab/research grade USB probes, but they were like $500 then. They were a actually good, but I still used 3 and took 2 out of three.

Since you have a co2 meter, you can probably just go off of that. Under 700 and your tank should be OK. If you are close to 400 then your pH is probably great.

 

[IntrinsicReef]

I dose vinegar during the day, which pulls it down to 7.8-7.9,

Since you are already dosing vinegar, have you thought of adding the vinegar to Kalkwasser? I mix up Kalkwasser with 45ml of vinegar per gallon of saturated kalkwasser, and I have been happy with the results.

, I was just thinking maybe the reason why I don't see a large effect from the fresh air to the protein skimmer is due to more gas exchange through the surface. I have an open top, and good agitation.

This is interesting to me. I could see the gas exchange of room air ( with elevated CO2) at the surface overwhelming the intake of outside air introduced by the skimmer. You might be on to something there.

 

[Randy Holmes-Farley]

This is interesting to me. I could see the gas exchange of room air ( with elevated CO2) at the surface overwhelming the intake of outside air introduced by the skimmer. You might be on to something there.

IMO, pH raising with outside air (or a CO2 scrubber on a skimmer inlet) is always limited by tank top aeration.

In the highest CO2 cases, better room air is a better plan than messing with a skimmer intake.

 

[IntrinsicReef]

IMO, pH raising with outside air (or a CO2 scrubber on a skimmer inlet) is always limited by tank top aeration.

In the highest CO2 cases, better room air is a better plan than messing with a skimmer intake.

Thank you for the confirmation. I have a 150 gallon (48"Lx24"W x 30"T) in my living room that has a wooden canopy and completely closed stand. It is vented by two 4.5 inch fans in the stand and one in the canopy. When our 3 person family would leave for the weekend, I would measure a significant pH increase. I ran an outside line to my skimmer and saw a .1 pH increase. I can see how this might not help with a large water surface area exposed to elevated room CO2 though.