Aging Water - Aerating

[BigTallV]

I've been aging my tap water for a small 5.5G tank by using a 1G bucket and either letting it sit a week or aerating with a single typical air stone on a little pump. So I took to this method for a larger 47G tank that I acquired and has been running for about 6 months.

I have 2 buckets that are 17L or ~4.5G each. I fill with tap water and aerate with a 4" bubble disc on each line from a Tetra Whisper 100 (dual outlet). These aerate fairly vigorously for the better part of a few days before I see a drop off in the chlorine level. I'm measuring chlorine level with a Red Sea Chlorine "Fresh Test" kit that was recently purchased from the local fish store.

To my surprise, I thought the chlorine would be dissipated within a matter of hours, or at minimum after 24 hours. I've confirmed it's chlorine and not chloramine as I've contacted the local water supply via telephone and enquired with the on-duty supervisor who formerly was in the acquarium hobby.

I've searched the forum on aging or aerating water and found most of the information leading to the fact that chlorine dissipates rather quickly providing there's some surface agitation (which is where the exchange is occuring).

Can you have too much agitation? What is going wrong here? I would have thought that agitating the water by way of a bubble disc and running the air pump fairly wide open would assist in being able to rid the chlorine in short order. It takes literally at least 3 or 4 days before it's down to 0.1 or 0.05ppm. By one weeks time it's at 0ppm.

My preference is to age the water, I'd rather not "add" things to the tank if I don't otherwise need to (i.e. dechlorinator or water conditioner). Any ideas on what is going on with the chlorine taking so long to hit 0ppm?

 

[rdd1952]

I have alwys heard that chlorine dissipates but have never worried about it since I use a dechlorinator. It's so cheap and a lot easier than trying to leave water standing which I definitely can't do for a 75 gallon tank.

 

[ziggyboy]

Chloramine will not dissipate as easily and some say it's not even possible to fully remove it by aging. Chloramine is used by some newer water plants to replace chlorine. Make sure your water provider only uses chlorine if you plan to age water.

More info here: http/en.wikipedia.org/wiki/Chloramine#Us...water_treatment

 

[rdd1952]

He stated in his original post that he has contacted the water company and there isn't any chloramine in the water.

 

[Tolak]

I'll bet the 4.5 gallon bucket is deeper than the 1 gallon bucket, and has less surface area to the volume of water. Try filling the 4.5 half way, aerate, and see what the results are. You may just need a container with less depth & more surface area.

 

[BigTallV]

He stated in his original post that he has contacted the water company and there isn't any chloramine in the water.

I also asked if there was any near future plans to convert to using chloramine, the answer to that was also "no". He (the supervisor on duty at the water supply station) specifically mentioned that another nearby city utilizes chloramine as their pipes are considerably older and the water has a much greater length to traverse to the residents homes. But ours is a "free chlorine" system.

 

[BigTallV]

I'll bet the 4.5 gallon bucket is deeper than the 1 gallon bucket, and has less surface area to the volume of water. Try filling the 4.5 half way, aerate, and see what the results are. You may just need a container with less depth & more surface area.

The 1G bucket is 7" high x 8" diameter, filled to about a 6" depth with water, whereas the ~4.5G bucket is 13" high x 12" diameter, filled to about 12" depth with water. The ~4.5G buckets are those white and blue Big Al's Maintenance Kit buckets (has "17LE0-2" embossed on the underside so I'm assuming that's 17 liter nominal capacity). All the buckets in question are located aside each other within the same room, so that rules out any variance in environmental conditions.

Intriguing thought on the surface area to depth. This goes toward the sizing of tanks and the surface area to capacity ratio. More surface area == more atmospheric interaction. I'll try that approach as you suggest and report back as I have 2 of the identical buckets and bubble rings of which is attached to the same dual outlet air pump.

/BTV

 

[Tolak]

I'm interested to see the results. My water supply has chloramine, and they vary the amount of chlorine & chloramine due to my source being a surface body of water, which is severely affected by weather conditions. I would also have to aerate a few hundred gallons weekly even if it only contained chlorine.

I looked into having a well drilled several years ago; the cost in no way justifies the end. I use Prime to treat my water in everything from show tanks to fry hatching & growout tanks. If the shallower water with more surface area doesn't work out you may want to look into adding just a slight amount of dechlorinator. A good water treatment also neutralizes heavy metals through chelation, these are something that aquarists should be concerned about, more so with well water.

**Edited to add, since I'm mutitasking & my brain is going several different directions**


There is also reserarch showing that in municipal water systems there are bacteria growing, and growing into quite a problem, that are similar to the nitrifying bacteria that convert ammonia to nitrite & nitite to nitrate. These bacteria are capable of converting chloramine to its components of chlorine & ammonia, then living off of the ammonia, leaving chlorine which aerates out much more easily & nullifies to some extent the addition of chloramine. It's a nasty circle for municipal water companies, but a sort of boon for some aquarists, who add water with chlorine & chloramine to their tanks with no aeration or water treatments, feeding these bacteria which break down chloramine, and letting the chlorine aerate out on its own in an aquarium which usually has a larger surface area to volume ratio than a bucket.

 

[andywg]

Also, a bubble wall will not be as good at surface agitation as a small pump aimed at the surface.

Perhaps you could try a pump as it will increase surface agitation over an air pump and should also stir water up from the bottom towards the top.

I know that with heavy aeration you can drive off chlorine quite quickly, that is why publc jacuzzis tend to be in an on/off cycle to prevent all the chlorine gassing off.

 

[Meds081603]

This is quite interesting. I have a 5 gallon tank in my kitchen that I do not use dechlorinator on. I have a clean 1 gallon jug that I put water in every night to sit out. Every day I do a one gallon water change with this water and no dechlorinator. I have never had issues. I am not sure what they put in our water but you can tell when they have added chemicals. It smells like straight bleach coming out of the faucet. I always thought 24 hours was enough time to remove the chlorine. Perhaps I will test the water out of curiosity before and after I wait the 24 hours....

I am going to research the effect of chlorine on fish a bit more as I have a decent sized pond with several large goldfish. The pond gets 4 or 5 water changes a year during the summer months and I never dechlorinate their water. They do not act sluggish or appear to be affected in any ill way after the water changes.

 

[backtotropical]

Also, a bubble wall will not be as good at surface agitation as a small pump aimed at the surface.

Perhaps you could try a pump as it will increase surface agitation over an air pump and should also stir water up from the bottom towards the top.

Surface agitation is the way to go IMO. Think if you had a pump pumping water out along the surface rather than some bubbles rising. More agitation, much better. You can't have too much surface movement. Movement in the water below the surface doesn't have nearly as much benefit.

 

[BigTallV]

Also, a bubble wall will not be as good at surface agitation as a small pump aimed at the surface.

Perhaps you could try a pump as it will increase surface agitation over an air pump and should also stir water up from the bottom towards the top.

Surface agitation is the way to go IMO. Think if you had a pump pumping water out along the surface rather than some bubbles rising. More agitation, much better. You can't have too much surface movement. Movement in the water below the surface doesn't have nearly as much benefit.

Agreed, it's the surface agitation that facilitates the exchange of gasses into the atmosphere above the water. A powerhead clipped to the bucket might be an idea here (probably a quieter one too). Having water sitting still in a bucket works too, is also the quietest - naturally, but probably takes the longest.

Alas, I have sunk cost in an air pump, tubing, check valves, bubble discs, buckets and not to mention dechlorinator. So doing a trial test with a powerhead is not likely to happen (maybe someone else on the forum can try that if they have one available). Regardless, it's water change night for my 47G tank, so I'll conduct the full-bucket versus half-bucket aerating test and see how that goes.