Never, Ever, Remove Your Airstone...

[hensonc4098]

Hi all,

I have been a member on here a good few months now, and had noticed that a lot of people ran their tanks without airpumps/airstones. Having always run our 2 tanks (100L and 35L) with them, I was curious to find out more. After reading many journals and posts, I had read several times the advice from well established people on these forums saying "you don't need an airpump - save yourself some money" etc. So while cleaning out the 100L last night, I suggested to my dad that we take out the airstone becuase I had read you don't need it and it's a little noisy. Being happy to have a bit more peace and quiet, he agreed and we disconnected it from the board that we connect the lighting, airpump, filter and heater to.
And at the time we were happy, because it was quieter...
However, this morning, I got up to find all our fish either floating around the tank or at the surface, in various states of uprightedness, all gasping for air. I immediately grabbed the other airpump and put that on full blst while I reconnected the other one. I was too slow for 3 of the fish that died: an angelfish, a columbian tetra and a loach. Luckily, I was just in time to save our 3 old silver dollars, who had been upside down at the top of the tank, hardly breathing. They are pretty tough things and recovered in about 15 minutes from me putting the 2 airstones in.
So far, none are showing any ill side-effects of their oxygen starvation, but I feel really bad for the ones that died, literally suffocated.
I was amazed at the speed that the oxygen was used up - simply overnight. But also I am confused at how many people run their tanks without problems without air pumps, yet my fish die overnight from not having any?!!!
Simply because of this experience, I would warn anybody to be extremely careful when removing an air pump from a tank, that you do not make the sme mistake that I did!

Claire

 

[Nick16]

i find this somewhat misleading?
1. airpumps put little oxygen into the water themselves as the bubbles are to large, a spraybar is far more efficient at that job. surface adjitation is what is needed. smaller bubbles dissolve quicker
2. Any oxygen that was in the water (however much that may have been as air pumps arent very good) wouldnt have been used up overnight, unless you have a high stocking (what do you have, tank dimensions, stocking)
3. Do you inject co2 into your tank at all?
4. i have run all my tanks without an airpump, i do own one but have used it about twice in emergencies or fry raising.
they are not needed if you have the correct set up (E.G good surface adjitation)

 

[Truck]

i run all my tanks with no air pumps...as nick says, the bubbles are too large to dissolve so really dont do very much for gaseous exchange.

i doubt it was this if im honest

did you disturb the substrate last night?

 

[hensonc4098]

The tank is a 100L hexagonal, so in that sense, not a lot of surface area for oxygen to dissolve, but still should be enough when we have the filter outlet creating surface agitation I would have thought? It isn't a spray bar, just a pipe but it makes a fair amount of ripples.
Tank stocking: 3 silver dollars (I know they shouldn't be in there, but it's my dads tank and he won't listen), 5 red eye tetras, 2 columbians, couple of ottos and corys and we did have a small angelfish...
No CO2 injection or added at all.

It's confusing

 

[Truck]

did you disturb the substrate?

 

[hensonc4098]

Substrate is just gravel, so wouldn't be gas bubbles causing poisonous whatsits...

 

[Nick16]

im more leaning towards an ammonia spike. That is a fair amount of stokcing for a small tank.
and if im right that tank is tall and surface area is tiny.

 

[Truck]

Substrate is just gravel, so wouldn't be gas bubbles causing poisonous whatsits...

did you disturb it?

 

[hensonc4098]

Not too bad a surface area, but maybe just not enough for the stocking level dad has?

Substrate disturbance - maybe when I was moving rocks... probably actually

 

[indigoj]

I've had the same thing happen - my theory is that if the fish have been used to an air pump then the removal of it can upset the ammount of oxygen in the water, if they have always been without then they should be ok.

My experience was when I swapped my internal filter for an external (mature - used all media from internal +some) I turned off the airpump as the spray bar should have been enough and within a couple of hours fish were keeling over - luckily only lost one - airpump back on - everything right as rain within 30 min.

Strange as the spray bar should be plenty but now I only ever turn off air pumps when I'm around to keep an eye on thjings.

 

[Sofia]

Interesting.

We had an air stone and I took it out the other week -the wall of bubbles wasnt doing it for me anymore- i've not had any problems.

 

[MartinD]

as long as there is sufficient surface agitation there is no need for an air pump. I have run multiple tanks both with and without air pumps. The tanks running with were because there was little surface agitation and vice versa.

I would guess that you didn't have enough air getting in to the water through agitation. The air pump does help - when the bubbles burst at the waters surface they introduce air into the water.

 

[hensonc4098]

Weird

 

[Nick16]

i think truck is on to a winner here, im betting is was an amonia spike after moving the gravel.
simply turning on the airstone afterwards helped gas some of the ammonia away.

 

[Truck]

right....seeing as you disturbed the substrate, you more than likely disturbed some anaerobic bacteria...when the bacteria comes into contact with oxygen it goes through a chemical reaction where the hydrogen sulphide that is in the anaerobic pockets take on oxygen to create sulphur dioxide

this will have more than likely depleted the tank of oxygen