Idea Of Aeration At Night?

[sophos9]

Hi,

As per the subject line, I'm aware that fish need 'an' oxygen level in the water (anyone know what it is?), I'm also aware that too much CO2 is not good.... I'm aware that plants use oxygen then spit out CO2 during the night

What I don't have a clue about is whether I should introduce some ripples in the tank for a few hours during the night?

Can anyone help

 

[nry]

During lighting hours, plants will use CO2, hence allowing you to keep the level 'static'. During non-lighting hours plants use little (if any?) CO2 so levels of O2 in the tank will rise, affecting the pH level, the pH change is the bad thing for the fish.

Aeration at night will dissipate the CO2 (aswell as oxygenating the water), reducing levels dramatically, and will stop CO2 levels rising hence the pH change will be minimal.

You don't always need to aerate at night, I guess it depends on whether you can put a timer on the CO2 system, or if the fish are not liking things at night.

Oxygen levels are not related or affected by CO2 levels, so high CO2 in itself does not reduce oxygen levels.


At least how I understand it!

 

[The-Wolf]

O2 should be at 4ppm
CO2 should be between 10-40ppm dependent on the amount of plants

 

[Dave Spencer]

Aeration at night will dissipate the CO2 (aswell as oxygenating the water), reducing levels dramatically, and will stop CO2 levels rising hence the pH change will be minimal.

I don`t believe this statement is correct.

I have a solenoid that switches my CO2 off with my lights, with no form of overnight aeration. During the lights off to lights on period CO2 dissipates to give a pH rise of around 0.4.

Aerating at night will drive off more CO2, giving a larger pH increase than in my tank, but I doubt whether it will bother your fish.

Other people inject CO2 24/7 without any aeration problems either.

Dave.

 

[prankster705]

wolf, how do you measure O2 ?

 

[sophos9]

Thanks for all the replies....

I guess the golden question is should I or should I not and how would I know if I should be?? Make sense

 

[The-Wolf]

wolf, how do you measure O2 ?

with an O2 test kit of course
Tetra, Sera, Salifert and TMC all make O2 test kits

 

[prankster705]

ok, thx... I guess I'll look around next time I'm in a fish shop... never spotted those before... never looked either though... Didn't think they exist... thx

 

[sophos9]

Cool, I've never seen an o2 kit before...

So should you aeriate or not....?

 

[Dave Spencer]

Do you have a particular reason for believing your O2 is low?

 

[sophos9]

Hi Dave,

Not sure really... I added new fish yesterday and a red tailed shark is spending a lot of time near the surface and the new tetra's are not moving a great deal. No fish are gasping at all.... wondering if its cus I have no circulation (spray bar against the side to stop it wrecking plants.

Just turned an eheim pump on and the fishes perked up a bit, it was not breaking the waters surface (very slight ripples at best) but was circulating the water?

 

[Graeme Edwards]

IMO you will be wasting your money buying an O2 test kit.

Look at you fish, they will tell you if you need to aerate your water.

If your fish are regularly at the surface then add an air pump on a timer for a few hours over night.
Please don't bother wasting hard earned cash on an O2 test kit!!
If in doubt add aeration, its nearly free, and will not have any negative effects on fish or plants over night!!!

 

[Dave Spencer]

I forgot to add Sophos, I work in an industry where O2 measurement is very important, but at the same time very difficult and costs thousands in test equipment.

An over the counter kit will be crap.

If your fish are looking distressed and gulping for air have a look at your CO2 levels (I think you are injecting, aren`t you?).

Dave.

 

[sophos9]

thanks for the info on o2 measurement... handy!!

CO2 output is 1BBS and using the 24hr PH test is measuring 25ppm

Fish are not distressed at all, its like they enjoy the current in the tank. I will run the eheim powerhead on a timer with the moonlights and see what happens

 

[BINKSY]

i do the same as dave, my co2 is on with the timer with the lights, i also have a siesta peroid during the day of 2 hours, which also gives the fish a rest from the co2, from doing this my fish are healthy and i have good plant growth, but as i have read here many times what works for one person may not work for another



Cheers Gordon