victoly Posted October 29, 2013 Share Posted October 29, 2013 The correlation (especially in the last week) isn't great, but I've noticed that as the weather cools, that i seem to have lower pH (ostensibly from something relating to CO2 concentrations in my house as a result of HVAC or the way the house is sealed.) I'm not too concerned about the trend, unless it continues to drop. I might have to bring in some external air into a bubbler. Anyone else noticing similar variations? Quote Link to comment Share on other sites More sharing options...
esacjack Posted October 29, 2013 Share Posted October 29, 2013 my tanks in the garage havent had much of a ph change at all with the cooler weather. So I'm guessing that it must be, as you said, related to CO2 concentrations. The tanks I have in the house are actually not monitoring pH outside of manual testing, but I can check and verify the differences in pH between my outside and inside tanks. Quote Link to comment Share on other sites More sharing options...
victoly Posted October 29, 2013 Author Share Posted October 29, 2013 and the CO2 concentrations are most likely related to human respiration combined with how well sealed the garage is. Quote Link to comment Share on other sites More sharing options...
jestep Posted October 29, 2013 Share Posted October 29, 2013 What are you logging your PH with? I haven't setup anything external and Apex lite only allow for displaying 7 days of data. Could export screen by screen into excel I suppose. Quote Link to comment Share on other sites More sharing options...
Timfish Posted October 29, 2013 Share Posted October 29, 2013 I've also seen the pH of a tank have noticiably lower highs and lows on cloudy days even though the tank was in a room with only north facing windows. It would be interesting to see the chart lined up with rainfall besides outside temps. Quote Link to comment Share on other sites More sharing options...
victoly Posted October 29, 2013 Author Share Posted October 29, 2013 weird bug with my apex, every once in a while, i get a 2014 data point which makes my charts go ape. i have my apex set up here:http://www.reeftronics.net/victoly/apex-history Quote Link to comment Share on other sites More sharing options...
victoly Posted October 29, 2013 Author Share Posted October 29, 2013 I've also seen the pH of a tank have noticiably lower highs and lows on cloudy days even though the tank was in a room with only north facing windows. It would be interesting to see the chart lined up with outside temps and rainfall Those temps are average outdoor temps. I postulate that it has something to do with how much the AC is running (positive pressure on the house maybe?), or how much time my family spends indoors/outdoors. Quote Link to comment Share on other sites More sharing options...
Timfish Posted October 29, 2013 Share Posted October 29, 2013 Off hand I don't remember which days we got rain most of the last, well, year. But the 13th is when ACL got rained out. So the 11th, 12th and the 13th it looks like the high pH reading for the days was pretty close to the the same then it dropped with the rain. Does cloudy or rainy weather have any effect at all on your system like I've seen on another? Or is it mostly how often you all are inside or how much your AC is running? (Or some average of those variables.) It will be interesting to see what happens as it cools off and your heat is running more. On the pH chart it gives a time with the date and the time stamp is gradually getting later. Is the time stamp given when the data is actually taken or just happen stance? My perception is you are getting quite a few data points throughout the day but if the time stamp is the actual moment the pH is tested the time of day might be a factor. Quote Link to comment Share on other sites More sharing options...
victoly Posted October 29, 2013 Author Share Posted October 29, 2013 Off hand I don't remember which days we got rain most of the last, well, year. But the 13th is when ACL got rained out. So the 11th, 12th and the 13th it looks like the high pH reading for the days was pretty close to the the same then it dropped with the rain. Does cloudy or rainy weather have any effect at all on your system like I've seen on another? Or is it mostly how often you all are inside or how much your AC is running? (Or some average of those variables.) It will be interesting to see what happens as it cools off and your heat is running more. On the pH chart it gives a time with the date and the time stamp is gradually getting later. Is the time stamp given when the data is actually taken or just happen stance? My perception is you are getting quite a few data points throughout the day but if the time stamp is the actual moment the pH is tested the time of day might be a factor. Could be lots of things, I'm going to use a CO2 meter at work to see if i can diagnose. In regard to the pH reading interval, not sure why the time stamps are funky, readings get taken every 5 minutes. 1 Quote Link to comment Share on other sites More sharing options...
Bogdan Posted October 29, 2013 Share Posted October 29, 2013 The opposite trend (lower temp - higher pH) would be morelikely if you believe this is linked with the CO2 concentration. In my case,when the summer is over and night temperatures get down to ~70 - 60ties I openwindows and let the fresh air in. I think the fresh air lowers the CO2 levelinside of my house (which increased over the summer with closed windows). Ifthere is lower CO2 level in the air then less is mixing/dissolving in the waterand less carbonic acid is forming. That should push the pH up, or so the storygoes. That is the very simplified mechanism; we know that there is many morefactors involved so the correlation is not so obvious. If you can measure the CO2 levelthat would definitively help. Quote Link to comment Share on other sites More sharing options...
jestep Posted October 29, 2013 Share Posted October 29, 2013 Just graphed the last 30 days, and mine is pretty stable, slightly increasing overall. I don't think we've messed with the thermostat which is only on AC right now, so I would say it's definitely colder overall in the house. Definitely isn't breaking 76 at the most. Pretty unscientific though on my end. Quote Link to comment Share on other sites More sharing options...
Timfish Posted October 30, 2013 Share Posted October 30, 2013 Just graphed the last 30 days, and mine is pretty stable, slightly increasing overall. . . It's hard to tell the dates but it looks like your pH had a noticable drop on the 13th like Victoly's when ACL got rained out. It's certainly reasonable to think the changes in the trend of pH daily highs and lows is associated with the changes in CO2 in the room the system is situated and seems to me the better explaination for the differences between Victoly and Jestep's charts. But considering photosynthesis in the corals is using up CO2 might not the corals reaction to weather changes influence the rate CO2 is absorbed? The most dramatic example I have of a coral responding to seemingly rather insignificant outside influences was a Bubble coral which opened and closed not with the cycling of the MH lights it was under but with the rising and setting of the sun. Even though the tank only got very brief direct sunlight each morning it closed up when the sun set irregardless of when the MH lights turned off. Quote Link to comment Share on other sites More sharing options...
Timfish Posted October 30, 2013 Share Posted October 30, 2013 And another explanation both Jestep and Victoly saw pH drops on the 13th is they both decided it was a good day to do a water change and really had no direct correlation to differences in CO2 levels or photosynthesis because it was a rainy day. Quote Link to comment Share on other sites More sharing options...
Neon Reefer Posted October 30, 2013 Share Posted October 30, 2013 Trying to determine the cause of the low pH as you are doing is the best start to correcting the problem if in fact one does exist. Your data does show you are begining to fall to the minimal acceptable normal range arounf ~7.7 -7.8. If you have a concern that there is a build up of CO2 in your home the best method to test for this is to take a sample of water from the display and aireate w/ a stone to completely aireate the water while in the house for a period of time (~ 1 hour) to reach an equlibrium of inside air with the sample. Measure it. Then take the sample outside and agfain aireate it to equlibrium with outside air and again measure it. Compare results to determine if the problem is high concentrations of CO2 inside the house. If pH on outside sample does not rise then there is no build up inside home. Maybe it is due to the weather but in any case opening a window or drawing in outside air would not solve the problem, Something to remember is that no matter what the concentration of dissolved oxygen and CO2 is in your water there is still a direct correlation to pH and Alk. At full oxygen saturation (which aquariums never acheive) the relationship is that where a meq/L of 4.0 Alk should have a pH factor of 8.4, and at high CO2 concentrations the same Alk should have pH around 8.05 which is still well within the acceptable range. Therefore increasing Alk numbers should have a direct relationship in raising pH numbers regardless of the root cause. And remember that buffers are not really going to raise Alk. But changing your 2 part to one w/ a higher pH value can be effective in dealing with low pH values. And better yet utilizing Kalkwasser works best as it will also help to lower the CO2. But both raises the pH without raising the Alk in relation to the calcium. Good luck Quote Link to comment Share on other sites More sharing options...
Planeden Posted October 30, 2013 Share Posted October 30, 2013 i think vic's explanation is the best. not having the A/C run is not bringing in as much outside air. so, hotter days are changing the air more than cooler days. i imagine in the coldest winter days it will start trending up as the heater kicks on more and more. jesteps tanks, being outside, are not affected by A/C so are pretty consistent regardless of outdoor temp. of course, this assumes your house is sealed well enough that there is a buildup of CO2. 1 Quote Link to comment Share on other sites More sharing options...
jestep Posted October 30, 2013 Share Posted October 30, 2013 I don't think I did a water change that day. The second drop was due to the outlet hose slipping off the return pump while we were out of the house. Generally, I use ph as a very general measurement and don't actively do anything to try and alter it. I learned from messing with CO2 planted tanks for a several years to more or less ignore PH assuming it's within some reasonable range. There's just too many factors that affect it to go chasing it anywhere. In this thread alone we're discussing water temp, ambient temp, ambient humidity levels, alk, AC usage, dissolved O2 and CO2 (both in tank and out of tank), and this doesn't take into account dosing 2 part, or 1 part, or kalwasser. 2 Quote Link to comment Share on other sites More sharing options...
Neon Reefer Posted October 30, 2013 Share Posted October 30, 2013 I don't think I did a water change that day. The second drop was due to the outlet hose slipping off the return pump while we were out of the house. Generally, I use ph as a very general measurement and don't actively do anything to try and alter it. I learned from messing with CO2 planted tanks for a several years to more or less ignore PH assuming it's within some reasonable range. There's just too many factors that affect it to go chasing it anywhere. In this thread alone we're discussing water temp, ambient temp, ambient humidity levels, alk, AC usage, dissolved O2 and CO2 (both in tank and out of tank), and this doesn't take into account dosing 2 part, or 1 part, or kalwasser. Amen Quote Link to comment Share on other sites More sharing options...
victoly Posted October 30, 2013 Author Share Posted October 30, 2013 I booted up an ambient CO2 monitor this morning. I'll let you know the results this evening after it's had a while to settle down. It hasn't been used in many years and I don't really wanna shell out the money to zero it out with nitrogen, so we'll see what kind of data we get. Quote Link to comment Share on other sites More sharing options...
victoly Posted October 31, 2013 Author Share Posted October 31, 2013 The results are in: Outdoor CO2 = 462 PPM, indoor CO2 = 1056 PPM. After having the windows open for 2 hours, I'm at 711 PPM. Quote Link to comment Share on other sites More sharing options...
victoly Posted October 31, 2013 Author Share Posted October 31, 2013 3 hours 650 and I'll stop the test there. Resume readings in the morning. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
jestep Posted October 31, 2013 Share Posted October 31, 2013 It's probably pretty close to accurate. I believe average is 400ppm now so being in a city it would be expected to be higher. I never realized that it would be double that indoors though. Quote Link to comment Share on other sites More sharing options...
(Bio)³ Posted October 31, 2013 Share Posted October 31, 2013 Hydro industry calls u.s avg 4-500 and china avg about 700 both outdoors. And with no plants to absorb it can easily double indoors. Often about 1200 indoors. Course we don't have fancy meters really Sent from my SAMSUNG-SGH-I337 using Tapatalk Quote Link to comment Share on other sites More sharing options...
victoly Posted October 31, 2013 Author Share Posted October 31, 2013 Closed up all the windows for the night (that rain!) and woke up to CO2 of ~1400! Something I've noticed on the charts is I believe that my pH is lagging behind the change in temperatures (and consequent change in HVAC usage?). You see the temp rising on the OP, and just now my pH is starting to rise as well. I think you have to have sustained change (i.e., small spikes dont seem to affect my pH because I don't aerate heavily). Also of note, check out my large pH DROP last night. Weird... Quote Link to comment Share on other sites More sharing options...
Timfish Posted October 31, 2013 Share Posted October 31, 2013 Also of note, check out my large pH DROP last night. Weird... Maybe the change in barometric pressure? Same thing happened on the 13th when we had a good storm go through. It also dropped a lot on the 17th but I don't remember if we had a big shift in weather. Quote Link to comment Share on other sites More sharing options...
victoly Posted October 31, 2013 Author Share Posted October 31, 2013 Also of note, check out my large pH DROP last night. Weird... Maybe the change in barometric pressure? Same thing happened on the 13th when we had a good storm go through. It also dropped a lot on the 17th but I don't remember if we had a big shift in weather. Maybe? Seems like a weird mechanism to affect pH though. For pH to DROP heavily, you would need there to be more CO2 dissolving. Maybe the high pressure is more conducive to having more CO2 dissolve? I'd be interested to see Jamie's data, although you may have to have had the windows open like I did, if that is in fact what made the drop heavy. Quote Link to comment Share on other sites More sharing options...
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