fresh air from outdoors to raise pH
 

a dwelling sealed up with people inside will drop aquarium pH due to increased CO2 levels. There was a thread a few weeks ago regarding running skimmer air lines to the outside in order to raise aquarium pH. How many folks have tried this and what were/are your results- is your aquarium running at a noticeably higher pH?
We have a houseload of people right now and my pH is running lower than normal. I just hooked up my skimmer airline to the outside and pH immediatly jumped from 7.14 to 7.16, but it might be due to the aquarium lights turning on. I don't know if the fresh air is having any effect- maybe it's too soon to tell.

alot of these posts pop up durring winter when house is all sealed up.i used to do have to do it as my tank was in basement.

My tank is infront of two windoes that are always open, and my ph never drops below 8

let's pretend open windows aren't an option :)

i run an air line outside and hook it to my skimmer works for me

Lol, opps my mistake, just thought it would help LOL

Tom tried this.

I wonder how well it would work to get a compressed air bottle filled with oxygen and have it regulated directly into your skimmer venturi? Seems like overkill, but so does running pipe to the outside.

The same company that makes mapp, and propane for torches also make oxygen(not pure but good for our purposes). You could set up some kind of a system that would give a constant stream of O2 into the skimmer via tubing. Just be careful not to use it anywhere near a flame. If you ran such a system for a few minutes and used a pH probe at the outlet of the skimmer to measure effect you should see a dramatic impact with in a minute or sooner (skimmer size dependant).

I have pH issues and have been using out door air for a couple of months with great results. I am worried about the winter time though.

you keep 2 windows open and the A/C running?

Gary if you are using a pH probe it may be time for a calibration also, just a thought ;) If you use Kalk maybe take a sample of it and test the pH to see what you get :)
**EDIT**
Check out this link this guy has had decent results :)
http://reefcentral.com/forums/showth...readid=1433717

thanx for the link.
my probe has been calibrated very recently and it does register the high pH of kalkwasser properly. Maybe I need to give the fresh air more time to raise pH of the entire system.

Hi Gary,
I have the luxury of having my sump in the basement,so it was easy to run an airline to the basment window and rig a piece of stiff insulation with a piece of screen to cover the opening in the galss block window and provide a screened air input for the tubing. In a DIY mood and with 20 minutes to spare, I tried it. Eventhough I wasn't sure I had a CO2 problem in the house.

My skimmer did not bubble well defeating the whole purpose by reducing the skimmer's oxygenation, probably because of the 10 foot length of small tubing.I could fix this by running a one inch or so pipe and reducing it down at th skimmer but I never did and just started dosing kalk instead with much better results.

If I were going to try this again, I would do the outside aeration test first to discern wether or not I have aCO2 problem in the house. As you probably know, you aerate some tank water and test the ph inside,then take some tank water outside , aerate it and test the ph. If there is a significantly higher ph outside then it might be wothwhile to hook the skimmer to an outside line.

Those numbers 7.14 don't seem at all right and are probalby related to a testing issue.

FWIW, those probes and the monitor itself can be very sensitive to any electrical interference at the outlet or in the water. They even react when the cord is in close proximity to other wires particularly ballst and wave makers.

Every time I close up the house and run the air-conditioner the ph drops. It's predictable. It was worse while running a calcium reactor. I haven't seen deleterious effects though. I pump in extra kalk and the levels are bumped slightly but by then the heat wave ends and the window get opened and ph rises. Alls good.

I guess a real simple solution is to crack a few windows, but of course that lets in some uncomfortable humidity.

Last night we opened the windows and the ph went from 7.98 to 8.19 with out any other changes.

Gary this is a really good link to give insite into CO2 and its effects on seawater.

http://cdiac.esd.ornl.gov/oceans/co2...ml#co2sysinsea

Would anyone know if extending the tube hinder the ability to suction air the way it would at normal length?

It would be good for me to run outside also due to the noise level my suction tube makes from my skimmer.

EMF is a *itch huh Tom? ;)

Also for those of you considering dosing O2 straight to your tank via the skimmer remember that 100% O2 is probably as corrosive as a 50mg/hr Ozone addition. So you will over time notice deterioration of the tubing and perhaps the acrylic in your skimmer if you do this... And as mentioned, Pure (or near enough pure) O2 is not something to be trifled with. An Oxygen fire is the worst thing ever, don't want that much fuel in your house going up real quick due to careless handling of it.

Personally, I agree with Tom that adding O2 directly to the tank is unfortunately not a good solution for driving out CO2. Ultimately calcium hydroxide scrubbing (kalkwasser) addition is the easiest measure by far of defeating ambient CO2. Using Outside air can work, but as Tom found, you can't just use long airline tubing as the pressure drop will be too much, gotta get a big tube to the tank then reduce it down just before introduction to the skimmer.

long airline tubing doesn't have a noticeable effect on air intake in my case. I'm using 25ft. of 3/8" ID rigid flex tubing on my Beckett skimmer and it hasn't (noticeably) effected skimmer performance. The true test would be to hook up something like an airflow meter to measure airflow but I don't have one of those things. The next step is to design some type of aircleaner/filter for the air intake. Right now the only thing filtering my outside air is some nylon window screen.

Any noticeable increase in pH?

LOL - I also did this about a month ago, I did see small raise in my ph and I liked the idea of introducing fresh air in the reef tank system anyways…

I like the idea of fresh air for the system paricularly since mine is in the basement near the workshop but how fresh is it? I'd have some concerns about where to put the intake, certainly not near areas where I might in a numb brained state spray weeds or bugs.

Gary, maybe th beckett venturi responds to air pressure changes in a less sensitive way(sucks harder) than the asm needle wheel set up.With the asm there was a definate fall of in bubble production. The hose I used was also 3/8 inches.

Gary, the pressure drop in 3/8" tubing is SIGNIFICANTLY lower over longer lengths than typical airline tubing of 3/16" or 1/4" diameter. The relationship of tube ID to pressure drop (per foot) is NOT linear. Its something more like logrithmic or exponential. So as your diameter gets smaller, the pressure drop will increase drastically. 3/8" is right around the "breaking point" for air at moderate flowrates, so it doesn't surprise me that this has worked well for you :)

I think we're all in agreement here- in fact, I was wondering what kind of effect a 25' 3/8" diameter hose would have on a needlewheel skimmer and Tom just answered that :)

My Beckett sucks hard. She's like an old 396 V8... raw muscle! There's no doubt it's working close to optimal. Maybe someday I'll get an airflow meter on 'er and find out exactly what type of pressure drop I'm getting from the long intake hose.
Without tweaking my pH probe I've gone from 7.14 to 7.63 but there are several other variables involved- four houseguests have left and I did a water change.
The bottom line is everything in the aquarium is looking better now and I don't have to entertain in-laws
:D

Sounds like a good day Gary. iIstill think your ph numbers are low especially since you are dosing kalk.