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YSS
01-27-2012, 03:28 PM
Ok, I understand that cold water (liquid) holds more oxygen than warmer water. I also understand that as the water temperature rises the gas is released. This is one of the reason why we see de-gassing issue during the colder seasons (I am not 100% convinced of this but I will buy it for the sake of arguements). Now, I always seem to get a lot more de-gassing (tons more of tiny bubbles) towards the end of the water change no matter how quickly or how slowly I fill the tank. The water temp from the tap isn't changing nor the tank temp. I have a couple of theories, but wanted to see anyone here knows for sure why this would happen.

DiscusOnly
01-27-2012, 04:10 PM
There are less splashing as you are closer to filling the tank to the top.

I posted it in one of my older post. With a combination of temp matching and using an extra filter housing, I eliminated almost all bubbles for my WC.

Van

Northwoods Discus
01-27-2012, 04:27 PM
The fact that the water is under pressure while pumped and then the pressure is let off would allow gasses to escape the liquid as well as temperature. That is why the storage barrel is not kept under pressure. Kind of like deep sea diving and the bends. Due to nitrogen forced into the blood by pressure. Then let off when coming up to the surface. If you come up too fast you don't breath it off and you get the bends (nitrogen bubbles in the blood and tissues ).

JamesHe
01-27-2012, 04:32 PM
The fact that the water is under pressure while pumped and then the pressure is let off would allow gasses to escape the liquid as well as temperature. That is why the storage barrel is not kept under pressure. Kind of like deep sea diving and the bends. Due to nitrogen forced into the blood by pressure. Then let off when coming up to the surface. If you come up too fast you don't breath it off and you get the bends (nitrogen bubbles in the blood and tissues ).

+1

jimg
01-27-2012, 04:54 PM
it is understood why the bubbles occur, his question is why at the end do they increase. Mine does the same regardless of how far away the hose is from the tank or how full it is, after about 5 minutes the water comes out of the hot faucet to a point where it's almost white. does the same thing just pouring it into the sink so the theory of air contact time I would rule out.

ExReefer
01-27-2012, 05:09 PM
I wonder if it's because towards the end of the water change your tank water is already super saturated and cannot gas off at the same pace as it can early in the water change.

Northwoods Discus
01-27-2012, 05:16 PM
Dunno?

PAR23
01-27-2012, 07:40 PM
There are less splashing as you are closer to filling the tank to the top.

I posted it in one of my older post. With a combination of temp matching and using an extra filter housing, I eliminated almost all bubbles for my WC.

Van

Hi Van,

Can you elaborate on how you use the extra housing filter to eliminate microbubbles or provide the link. Thanks

4discus
01-27-2012, 07:54 PM
Yes Van,

I am curious also. Thnx

Darrell Ward
01-27-2012, 08:34 PM
Bubbles from water changes have never harmed any of my fish over the past 2 or 3 decades, so it's not really something I worry about. I think it would only be cause for concern if the whole tank were "frothy".

YSS
01-27-2012, 09:24 PM
Bubbles from water changes have never harmed any of my fish over the past 2 or 3 decades, so it's not really something I worry about. I think it would only be cause for concern if the whole tank were "frothy".

If I fill up my tank quickly during the cold seasons, my discus stress out big time even when I do less than 50% water change. When I fill the tank up slowly, I mean slow, my fish are fine even when I do over 75%. I take almost two hours to fill up the tank when I do a big water change. But even when I fill up slowly, the last 10%, I see significant more gas bubbles. I don't know why.... But it doens't seem to bother my fish so I am not too concerned.

ExReefer
01-27-2012, 11:58 PM
I recently started pouring water from the faucet directly into a 5 gallon bucket and pumping the water from the bucket to my tank. I just match the temp and keep the water flowing from the faucet until my tank is full. I get much less saturation this way, but I never do more than 50% WC in the winter, so I have to do more WC's overall. The fish are not stressed after this. When I used to go from tap to tank they were stressed big time and my tank had millions of microbubbles.

This is not a new method. I read about it somewhere in here a while ago. The splashing and exposure to the open air in the bucket gasses off the water a great deal. It's not as good as aging, but it's pretty close in my experience.

DiscusOnly
01-28-2012, 02:30 AM
Hi Van,

Can you elaborate on how you use the extra housing filter to eliminate microbubbles or provide the link. Thanks

Peter,

Post #14

http://forum.simplydiscus.com/showthread.php?87536-Poret-Foam-Micro-bubble-reducer&p=753574&highlight=#post753574

YSS
01-28-2012, 10:32 AM
I recently started pouring water from the faucet directly into a 5 gallon bucket and pumping the water from the bucket to my tank. I just match the temp and keep the water flowing from the faucet until my tank is full. I get much less saturation this way, but I never do more than 50% WC in the winter, so I have to do more WC's overall. The fish are not stressed after this. When I used to go from tap to tank they were stressed big time and my tank had millions of microbubbles.

This is not a new method. I read about it somewhere in here a while ago. The splashing and exposure to the open air in the bucket gasses off the water a great deal. It's not as good as aging, but it's pretty close in my experience.

Getting some interesting ideas. So, if what you are doing works well, then what about filling the bucket from the tap and let the water spill in to the tank from the bucket? That would be similar to what you are doing right?

brewmaster15
01-28-2012, 11:02 AM
Hi Guys,
Just to clarify some things here.. not an expert but these are my understandings and experience

It really depends on your source water...If your water is municipal, it generally will have far less "gas" in it (though that will vary also) ...however if your water is well water...you could have very high amounts...as the water is technically pressurized underground more again variable on the depths the well is drawing from and the particular aquafer. With this in mind...what works for one person may not work for another depending on the dissolved gas.

Be careful when you say " gas"... Some Gases can be very dangerous... Its not necessary the bubbles themselves that are the problem...its the content of the bubbles. Heres an example.. I have a well. I draw my water from and read the pH from the tap..its generally between 6.0 and 6.2 most of the year..winters it can be lower. Its loaded with CO2 as the gas. if I age my water its pH jumps to 7.8. so the pH swing will be from 6.0 to 7.8 in a few hours , some could and do argue thats a problem in itself... but the real problem in my case is every fish in the tank will be at the top gasping for oxygen if I do a major water change with unaged water from the tap.,,,its like overdosing the fish in a planted tank with CO2 dosing.

hth,
al

jimg
01-28-2012, 12:04 PM
I have heard and read that the tiniest of the bubbles get on the fish's gills and block them.

PAR23
01-28-2012, 01:04 PM
I recently started pouring water from the faucet directly into a 5 gallon bucket and pumping the water from the bucket to my tank. I just match the temp and keep the water flowing from the faucet until my tank is full. I get much less saturation this way, but I never do more than 50% WC in the winter, so I have to do more WC's overall. The fish are not stressed after this. When I used to go from tap to tank they were stressed big time and my tank had millions of microbubbles.

This is not a new method. I read about it somewhere in here a while ago. The splashing and exposure to the open air in the bucket gasses off the water a great deal. It's not as good as aging, but it's pretty close in my experience.

I though about trying this and wonder if it would actually work. Good to know it is another option.

Jhhnn
02-09-2012, 01:24 PM
The fact that the water is under pressure while pumped and then the pressure is let off would allow gasses to escape the liquid as well as temperature. That is why the storage barrel is not kept under pressure. Kind of like deep sea diving and the bends. Due to nitrogen forced into the blood by pressure. Then let off when coming up to the surface. If you come up too fast you don't breath it off and you get the bends (nitrogen bubbles in the blood and tissues ).

Everybody's water is different, and municipal water is often a very highly processed commodity. Denver water certainly is, and in winter time, it's very cold as it's processed & pressurized for distribution. It has a lot of gas molecules in it for that reason, chiefly nitrogen. When heated, the gas wants to escape because of lower solubility at higher temps, but can't because of pressurization- it's super saturated with gas, like soda or beer. When the pressure is released, like putting it into an aquarium, the gas aggregates into microbubbles & then larger bubbles over time. It also escapes directly at the surface. It's not instantaneous, so it seems like there are more bubbles towards the end of a water change because enough time has elapsed for them to get big enough to become visible.

With our fish, there's a constant exchange of molecules across their tissues, both water & gas, particularly their gills. When the water is super saturated with gas molecules, those microbubbles can easily form on the wrong side of fish membranes, causing the equivalent of the bends, as Northwoods discus suggests. The bubbles we can see won't harm the fish, but are a symptom of the super saturated condition that can. A former contributor, Yasmeena, apparently lost some fish due to this & posted pics of some with bubbles in their fins some while back. Maybe she's back? Dunno...

I have the ability to age water, so I do, and went to elaborate lengths so that I could, but not everybody is so fortunate. A lot of different ideas have been posted, like the bucket method, splashing the water through very coarse sponge & so forth- anything to increase the surface area & exposure time before water enters the tank, and to agitate the surface as that happens. I've often considered that a U-tube cut to the right length with a flat plate attached at 90 degrees to the water flow ~1/2" from the end would cause the water to spray out in a fan pattern entering the tank, radically enhancing gas exchange as tap water entered the tank, which is really the whole point of aging and aerating water, as well- to get the gas balance right before water goes in the tank...

YSS
02-09-2012, 01:30 PM
You might think this is strange, but I noticed I get less bubbles towards the end when I vary the amount of water coming out of the tab. I haven't really given much thoughts on why, but I increased the water flow towards the end of my last water change and I hardly noticed any water bubbles whereas in the past, even with very low flow rate, I was getting tons of bubbles. So many, it almost looked milky.