Trachyphillia g. ?

[stonycorals]

How do you support that position? It's pretty much the exact opposite of what you should strive for.

I support that position by simple logic and experience. Sure it'd be great to not have any swing whatsoever. However, naturally the pH swing as CO2 enters the water during night due to respiration and the absense of photosynthesis. During the day, it is the opposite, CO2 becomes depleted due to photosynthesis, especially when using any sort of refugium, or when the tank has abundance algae. This also occurs when the coral and clam stocking levels are high.

This assumes that you have limited gas exchange though. When aquarists have under powered skimmers, gas exchange is less than optimal and quite often resulting in pH fluctuations.

So what does the typical aquarist do then? They dump a lot of buffer into the tank that temporarily moves the pH, but causes swings in alkalinity, which IMHO is one param you don't want to fluctuate. Then starts the battle to maintain alkalinity, calcium, and magnesium levels as the aquarist sees the calcium go down due to adding all that buffer to increase the pH. But Calcium isn't the only ion to precipitate as a salt of carbonate, magensium does as well.

The pH of reefs also fluctuate due to the photosynthesis cycle, but it's not as extreme. Why? Because God isn't dumping buffers into the reefs to get the pH up. There is a natural pH fluctuation in our tanks and on the reefs.

Now, if you want a stable pH (meaning less than .2 daily fluctuation), you have two options, that do not involve adding any buffers/chemicals to our tanks. First, add a refugia, I've not run one, but since the pH fluctuation is cause by photosynthesis, put the refugia on a reverse cycle and this should do it. I'm saying should because I've not used a refugia before. The second, and one that I've had many years experience with, is using a good skimmer that provides excellent gas exchange. I've used downdrafts for many, many years and my pH does not move, it stays at 8.1. I know needlewheels are popular, but they simply do not process enough water to provide that level of gas exchange.

pH is one of those params, like temperature, that the hobbyist is convinced that they must be stable. Of course, there are a bazillion of buffer products out there that promises to maintain a pH level of 8.3 if you add so much of it, but your fighting a natural cycle. If you look to the reefs, there are natural, daily fluctuations. I'm more concerned about maintaining a stable alkalinity level than anything else.

 

[steve-s]

Your approaching this as a means of toleration or hobbyist acceptance of what's become popular. I can assure you, in terms of pH, this does your animals/system no service.

CO2 is atmospheric and easily equalized. As long as gas exchange remains optimum, there is absolutely no reason for large swings in pH. It should not be considered acceptable by any stretch of "experience". If anything, experience should have taught you it is easily correctable and avoidable. We don't relay information here to help people continue to do things wrong or perpetuate false assumption, we do so to eliminate it. It comes down to providing information for the hobbyist to do what's in the best interest of the animals they keep, not solely their desire to find justification and do as they will.

The pH of reefs also fluctuate due to the photosynthesis cycle, but it's not as extreme. Why? Because God isn't dumping buffers into the reefs to get the pH up. There is a natural pH fluctuation in our tanks and on the reefs.

The pH of reefs does not fluctuate even close to what your suggesting is acceptable, quite the opposite. A hobbyist that realizes proper waste management, bioload vs biocapacity and that proper pH should not be controlled chemically often does quite well in the hobby having very few losses in the long term.

I grasp why so many blindly accept this as the norm, what I don't accept is that it should be blindly repeated.
So while you have explained why you believe these wild daily swings happen, I do not see a reason for it's acceptance!?!

 

[stonycorals]

Your approaching this as a means of toleration or hobbyist acceptance of what's become popular. I can assure you, in terms of pH, this does your animals/system no service.

CO2 is atmospheric and easily equalized. As long as gas exchange remains optimum, there is absolutely no reason for large swings in pH. It should not be considered acceptable by any stretch of "experience". If anything, experience should have taught you it is easily correctable and avoidable. We don't relay information here to help people continue to do things wrong or perpetuate false assumption, we do so to eliminate it. It comes down to providing information for the hobbyist to do what's in the best interest of the animals they keep, not solely their desire to find justification and do as they will.



The pH of reefs does not fluctuate even close to what your suggesting is acceptable, quite the opposite. A hobbyist that realizes proper waste management, bioload vs biocapacity and that proper pH should not be controlled chemically often does quite well in the hobby having very few losses in the long term.

I grasp why so many blindly accept this as the norm, what I don't accept is that it should be blindly repeated.
So while you have explained why you believe these wild daily swings happen, I do not see a reason for it's acceptance!?!

So you're saying that reefs don't fluctuate .2 points daily or slightly more (8.0 - 8.4)? I'm not perpetuating any 'falsehoods', the bottom line is that reefs do fluctuate, are you going to say that temperatures don't fluctuate daily on the reefs, too? In one of my first acro tanks, I used kalk and a nilsen to maintain high pH over the course of a day, the tank swung from 8.6 to a low of 7.9 when the lights were off. This was back in the day, and I had the latest venturi skimmer, but my acros were growing an 1" + per month. Considering that the issue related to lower pH is calcification issues, there were clearly none here.

If you read my post, I'm not advocating maintaining the pH by using any chemicals, the exact opposite. If you got that out of my post, there is a communication issue then. I haven't put commercial buffers in my tank since the early 90s. I only use Ca Rx or two part. But that is what happens to the typical aquarist, they spend time trying to manage pH through the use of buffer products only to find out later that they are having issues maintaining calcium or that their magnesium levels are low.

You're completely missing my point. In most tanks, gas exchange isn't happening optimally and therefore most are experiencing large pH swings. I've used skimmers that do provide the gas exchange, I do not have any pH swings at all.

 

[steve-s]

You're completely missing my point. In most tanks, gas exchange isn't happening optimally and therefore most are experiencing large pH swings. I've used skimmers that do provide the gas exchange, I do not have any pH swings at all.

I have missed nothing at all. The underlined sentence is exactly the problem and is also the solution. Knowing why they fluctuate gives us clues on how to fix it so it does not continue. To say that they are to be expected and not an issue to be addressed is incorrect. However it's solved whether that be with equipment upgrades, changes to the system and/or bioload/capacity is important to the long term success. As long as it's solved and not solved chemically.

You've gone from...

Unless your pH is swinging from less than 7.8 to more than 8.5, your fine.

to...

So you're saying that reefs don't fluctuate .2 points daily or slightly more (8.0 - 8.4)?

So we have made some progress

And FWIW, a two part liquid is a buffer

 

[stonycorals]

I have missed nothing at all. The underlined sentence is exactly the problem and is also the solution. Knowing why they fluctuate gives us clues on how to fix it so it does not continue. To say that they are to be expected and not an issue to be addressed is incorrect. However it's solved whether that be with equipment upgrades, changes to the system and/or bioload/capacity is important to the long term success. As long as it's solved and not solved chemically.

You've gone from...

to...

So we have made some progress

And FWIW, a two part liquid is a buffer

Define progress...

Part of the problem though with 'solving' the pH 'issue' if it is related to gas exchange, is that your atmospheric levels of O2/CO2 during the summer and winter may be skewed due to having the house closed up, skewed toward an increase level of CO2. Another part is the 'ratings' skimmer companies place on their skimmers. Talk about skewed, some types more than others. If I would run an NW, I'd take what they say and divide by 4 or 5, they don't process enough tank water to make gas exchange happen( exception would be a BK). The downdraft or becketts are much better.

I have maintained multiple systems that exhibited 'large' pH swings 7.9 - 8.5, while my interests have largely been sps related and I've seen no decreased growth rates. But I've also had consistent alk levels, NSW levels ~7 dkh. My concern with hobbyist measurements with pH is that the assumption is made about pH probes as a good and reliable measure. In fact, pH probes start to lose their calibration withint 2 weeks. Therefore, the hobbyist goes to the LFS to buy a borate-laced buffer that promises to buffer at 8.3, when that doesn't happen, they add more until their alk is 15dkh, and they've got precipitated calcium carbonate all over the glass, pumps etc. and to boot, they can't seem to get their ca back up.

To me the param that is of utmost importance is alk. If that is stable, your tank is going to do just fine. Assuming everything else is within acceptable ranges, your pH will be fine.

 

[steve-s]

Define progress...

Your statements are becoming less general and more specific!

The problems you keep stating are the same that many have and the solutions are almost always the same. Improve the conditions creating it. It is often just as simple as it sounds. The exception being knowing what's creating it. I'm not sure why you are stuck on skimmers though, they would not be advantageous if atmospheric CO2 was elevated with the claim you make (Summer/Winter). It would actually cause more CO2 to be injected into the system further suppressing pH unless hooked up to an outside source. What does O2 have to do with it?

The easiest solution is open a window and exchange the air. It does not require the window to be open all day or hours a day. Only that outside air be exchanged for inside air. Do it a few times a day, you'd be surprised what a simple solution like that can have.

That you have had no ill experiences with poor pH is a blessing but that should not mean it's something to support in other/future hobbyists. In doing so we encourage misinformation. There is one adage that I personally loath but I feel it's important to note here...

"The absence of evidence is not evidence of absence"

Mull that over a bit.

In regards to the alk, yes, there we are agreeable. The greater more stable the alkalinity, the less like the problems with pH or at least dramatic drops. You'll find though that 3-3.25 mEq/l would be more beneficial, especially in a CO2 problematic tank. The measuring of pH is also a dogs breakfast if not monitored with properly functioning equipment. Again though that goes to us as hobbyist knowing better and passing on the correct information.