CO2, Ph and al that goes with it

[jwoyshnar]

As many of us battle every fall and winter i started out this fall forgetting like always about ph drop and fluctuation with turning the heat on in Pennsylvania and the effects of doing so. My ph was going from 8.2 down to sometimes 7.6 at night. Burning coal really affects this too as you could imagine. Well this year i ran an extension tube from my skimmer out the window and my Ph stays right around 8.2. Do any of you run your skimmer intake outside and if you do, what does your setup look like? My girlfriend isnt happy about the hose going out the window so i have to come up with something.

 

[Randy Holmes-Farley]

Limewater might be a good bet if the hose is an issue.

 

[swck1]

I was about to post the same question, I have heard of people using co2 scrubbers, but not cheap and I was thinking about you idea of running a skimmer line outside. open window?:lolspin: and atleast for me dripping kalk doesn't help much in a closed up house

 

[Randy Holmes-Farley]

There are many threads on scrubbers (and hose lines to skimmers) in the chemistry forum. Scrubbers can work, but are expensive and sometimes not as effective as desired if the amount of air being used in a skimmer is high and CO2 is substantially elevated.

 

[Mandragen]

Who is al?

 

[Randy Holmes-Farley]

Who isn't?

 

[Mandragen]

true story

 

[nuclearheli]

CO2 scrubbers on your skimmer are not expensive and very effective at removing the CO2 from the intake air stream. I have a rather large skimmer which sucks a ton of air without any issues.

As far as the cost this is my first version of the scrubber. It's a simple piece of PVC pipe, a toilet bowl flange mounted upside down, and a shower drain. All components from Lowes, less than $20.

Just because I wanted to make it cooler and easier to see if the media was used up I purchased parts on-line and rebuilt the scrubber (below). That was a little bit more expensive, I believe around $50.

As far as the media is concerned I purchased a 5 gallon bucket of Soda Lime from AirGas for $100 shipped to my door. That was about 1 year ago and I am still using the same bucket. I change my media about once every 6 weeks.

You can see the blue color in the second picture as the media gets exhausted. In some respects this is more effective than using outside air which may still contain CO2. The scrubber removes almost all CO2 from the air stream. Remember, all that blue you see in the second picture is CO2 that didn't make it into your tank.

BUT like all of us installing a scrubber on the air intake of your skimmer only solves part of your problem. You are still getting a significant amount of CO2 exchanging with the surface of your DT, depending on the CO2 levels in the house and those in the tank. The only thing to do for that is bring fresh air into the room where the tank is located.

Keep in mind however your skimmer is a great source of oxygen for your water and putting a CO2 scrubber on the air intake is a great start and just makes sense.

 

[Randy Holmes-Farley]

Many people find the media much more expensive than you in therms of dollars per day.

 

[nuclearheli]

Many people find the media much more expensive than you in therms of dollars per day.

That's interesting and a bit perplexing to hear you say that. As a huge fan of your publications, many of which I have spent hours reading, and also a man of science for all of my life, I find it strange that you think a simple and effective "partial" solution to CO2 is actually expensive.

So I did my own calculations based on experience. I can go through the math but I am sure you don't care about that. The actual cost of running the CO2 scrubber in my experience amounts to approximately $0.15/day, real life data. That in my opinion is miniscule in comparison to the total daily cost to run a modestly large reef tank. I have not considered the cost of building the unit because I don't consider even $50 to be significant given the fact that I must have well over $10k invested in equipment in my system.

What is worth looking at when considering the total cost to operate a successful reef tank, after reading through your library of advice, is the cost of your recommended supplements, additives, and media. Now don't get me wrong, I attribute the current success of my tank, corals and fish, to advice and techniques taken from your tutorials. But even you must admit that by taking your advice on things like supplements, additives and media one spends considerably more money on a daily basis keeping a successful reef tank than an individual that simply ignores you advice.

I don't buy into all of your advice, I am sure even you understand that. It's great that you can put the theory and the science into words that a novice can understand, but you know as well as I do that science (chemistry) in theory does not always yield the same results when put to practical use. My practical experience and real world data over the course of more than a year is conclusive. When I run the CO2 scrubber I have a positive result and effectively reduce the CO2 in the system, as indicated by a more stable and higher pH. To prove it's worth the money to me I have intentionally shut down the CO2 scrubber several times to compare the data. I think it would be worth while for you to add CO2 scrubbing as an inexpensive and effective way at reducing, not eliminating, CO2 as a potential source of low pH values.

Regardless I have learned a great deal from your lessons and writings. Thank you.

 

[Randy Holmes-Farley]

That's interesting and a bit perplexing to hear you say that. As a huge fan of your publications, many of which I have spent hours reading, and also a man of science for all of my life, I find it strange that you think a simple and effective "partial" solution to CO2 is actually expensive.


I base that on some reports from folks who claim the material depletes very rapidly in their hands. Others say it lasts longer. The indoor CO2 level and the air flow rate through the media will determmine how long it lasts. The surface area of the material may also have an impact.

How much that media costs depends on what materials you buy. Like all things, some are more expensive than others.

However, by comparison to open windows or limewater using bulk calcium oxide or hydroxide, scrubbing is often going to be more expensive.

Here's an example of a thread discussing costs:

http://www.reefcentral.com/forums/showthread.php?t=1714932

from it:

"Jeremy's lasted like 2 weeks = ~ $800.00 / year. Even if it did last 1 month that is still ~ 350 / year."