Fizzy water

[Phish Tank]

I'm not particularly worried about it, but I am curious. My tank is always fizzy for 10-15 minutes when I am filling it. Why?


I use municipal tap water for water changes. Tap is roughly 5 dGH and 2 gKH. Tap TDS is 50. Tank has CO2 drop of around .7, and PPSPro dosing. Degassed PH around 7.4.

 

[RickyV]

Mine does this too but I noticed it only does it from the hot water line, the cold water doesn't do this. Not sure what it is.

 

[Mr.Shenanagins]

I have similar experiences. From what I’ve learned, it could be the high mineral content of heated hard water causing the brief cloudiness, or, trapped air manifesting into tiny microbubbles with the pressure shift from cold to hot.

 

[Phish Tank]

So @RickyV i think it is the hot water. I filled up two test vials, one hot and one cold. Hot one had the micro bubbles, cold did not.

 

[RickyV]

So @RickyV i think it is the hot water. I filled up two test vials, one hot and one cold. Hot one had the micro bubbles, cold did not.

I asked chatPGT and it said it may be because of the reduced solubility of gases when the water is heated and the high pressure in the water heater caused from thermal expansion.

 

[Pepere]

I asked chatPGT and it said it may be because of the reduced solubility of gases when the water is heated and the high pressure in the water heater caused from thermal expansion.

If Chat GPT reflects AI in general we have less to fear from AI than some worry about…. AI has precious little ability to discern between right and wrong information. What we have to worry about is people believing it…

In a properly installed water heater, if the building has a backflow preventer to prevent household water from being pulled back in to the water mains, then an expansion tank will be installed into the water feed line to take up the thermal expansion.

Warmer water can not hold as much gas as cold water can. Under pressure it can hold more gas than at low pressure. The hot water when it is released from pressure has microbubbles form.

However cloudy water can also be from minerals.

Fill a glass with hot water. If it is cloudy and clears from the bottom moving to the top it is gas bubbles. If it clears from the top to the bottom and takes longer to clear it is something settling out…

 

[Phish Tank]

It definitely clears from bottom to top, so it’s micro bubbles. And we do have a thermal expansion tank right above the hot water tank. Thanks @Pepere. Mystery solved.

 

[Pepere]

It bears mentioning that if anyone goes in their basement and does not see an expansion tank and figures they can install one on their own, that it is imperative to make sure it is one rated for the pressures it will see. There are expansion tanks designed for domestic hot water supply and expansion tanks designed for low pressure boilers expansion needs. Install a boiler expansion tank on a domestic hot water tank, and set up a video camera to film your very own mythbusters video! The reaction can be quite energetic.

If you are not sure, hire a professional from a reputable company.

 

[Koan]

 

[Pepere]

Clip above is a water heater BLEVE, Boiling Liquid Expanding Volume Explosion. This is much more devastating than what happens when the wrong expansion tanks is used and fails, as the failure point is well under the boiling point. But a failing expansion tank is not something I would like to be in close proximity to.

I tried to find a photo online of one that failed and was not successful, but I have seen one that did fail catastrophically. The tank in essence has a top and bottom half with a rubber bladder in the middle andthe two halves are seamed. My local plumbing supply shop had a new counter rep who sold an expansion tank to a customer and did not know to ask what application he needed it for. The customer installed a low pressure tank on his hot water heater. It worked fine for a month before fatigue set in and it failed. The bottom half completely dissasembled from the top and rocketed to the water heater underneath it and did significant crush damage to the bottom of the expansion tank and to the top of the water heater. The store ended up replacing both items and paying for professional installation and clean up damages for the water gushing out of the system..

But no wheres near as damaging as a BLEVE

BLEVE’s are prevented by temperature and pressure relief valves on the side of the tank and boiler. These should be opened yearly to drain water from a bit and ensure the seal still stops water afterward. If you have a leaking one, having it replaced is money exceedingly well spent. They fail with time and start leaking, but leaking can also be caused by other faults, such as a waterlogged expansion tank….