The Planted Tank Forum banner
1 - 10 of 10 Posts

·
Registered
Joined
·
517 Posts
Discussion Starter · #1 ·
I've read what wiki has to say about stagnant water.
Water Stagnation

So there are some fish that live in stagnant water, most commonly known is the betta I'd assume.

So.. I've read in a lot of posts in various forums, including here, that stagnant water will kill fish.. but I've yet to see an explanation to why that is. I ask because I have a fish tank with water sitting still. I thought that's what aged water is.. but no.. that's just stagnant water hah. So I'm wondering why my fish will die if I put them in there and if I can just put a power head in there or something to get the water moving to make it fish safe again. Or will this only function as a betta tank till I change the water.

Any input appreciated
 

·
Registered
Joined
·
695 Posts
uhhh bettas can live in stagnant water but thats only because the breathe air from the surface. I think stagnant is way different then black water though. Black water is caused by dying leaves and organisms in the water. Stagnant means that the water isn't moving but you can create a tank where theres no water movement and you don't do water changes but you have lots of plants and top off your tank when water evaporates. Plus you didn't do anything to the water right ? its basically clean and free of bacteria and you did remove the chlorine and chloramine right? I would still start with new water lol .
 

·
Registered
Joined
·
1,681 Posts
I've always thought of stagnant water as a small body of water with no circulation of any kind, basically still water. No current or agitation, no oxygen. No oxygen, fish die. When you age water, you are supposed to use water pumps or powerheads to keep the water moving.
 

·
Registered
Joined
·
517 Posts
Discussion Starter · #4 ·
hmmm hmmm hmmm. well now i know. but yes, the water has been sitting perfectly still. clean as when it left the faucet. but i guess i'll drain it and refill it... 50 gallons.. uggh. i need to get a python or something. thanks for the help
 

·
Registered
Joined
·
1,666 Posts
hmmm hmmm hmmm. well now i know. but yes, the water has been sitting perfectly still. clean as when it left the faucet. but i guess i'll drain it and refill it... 50 gallons.. uggh. i need to get a python or something. thanks for the help
You can always try the smell test. If it smells like swamp you need to do large WC and circulate.
 

·
Registered
Joined
·
644 Posts
Gouramis are also able to live in stagnant water because they're labryinth fishes that have a special lung-like organ that allows them to breathe at the surface. Like others have said, one major contributing factor is the lack of agitation and inflow of oxygen that kill the fish.
 

·
Registered
Joined
·
1,032 Posts
So.. I've read in a lot of posts in various forums, including here, that stagnant water will kill fish.. but I've yet to see an explanation to why that is.
Stagnant water has little to no dissolved oxygen.

Fish do not breath water. They breath oxygen which is dissolved in the water. If the water has little to no dissolved oxygen, they suffocate.
 

·
Registered
Joined
·
517 Posts
Discussion Starter · #9 ·
Thanks for all the different answers! Someone told me yesterday that stagnant water has no bacterial change. i'm guessing that would lead to a buildup of ammonia and give me that smell BlueRam mentioned.
 

·
Registered
Joined
·
1,032 Posts
There's plenty of bacteria in stagnant water, but it's what's called anaerobic bacteria. "Anaerobic" means not using oxygen, and that's actually a misnomer. Anaerobic bacteria does need oxygen. But it has the ability to take oxygen from nitrate (NO3) and sulfate (SO4). Nitrate reduction isn't a problem, as the only by product is nitrogen gas. But sulfate reduction produces hydrogen sulfide (H2S), which smells like rotten eggs and can be toxic to fish at high enough levels.
 
1 - 10 of 10 Posts
Top