[Nazdaq]

Lost 2 cardinal tetras, one a couple of days ago and one tonight. Could it be the co2? I was told as long as the fish is not at the surface or floating around they are probably ok. But they all do breathe more rapidly (especially my tetras) when co2 has been on for a couple of hours. I have decent surface agitation. Coincidence or co2? None of my other fish or catfish seems affected except for a little more rapid breathing.

 

[mistergreen]

A would turn down the CO2 a little to see any more deaths occur.
Do you know how much CO2 you're injecting?

 

[Nazdaq]

A would turn down the CO2 a little to see any more deaths occur.
Do you know how much CO2 you're injecting?

Not sure how many grams per day, dropchecker shows green and there is a good mist going on.

 

[No.92]

What's the size of your tank and how are you injecting co2?

 

[PlantedRich]

It could be the CO2 or it could just be that small fish die easy. I do not suggest waiting for the fish to swim at the surface as when gassing mine, many did not go to the surface but just settled to the bottom. None died as I was here to spot the trouble but they were very close.

 

[Nazdaq]

it's a 240 L tank and i'm injecting co2 at a pressure of 35 psi

 

[No.92]

it's a 240 L tank and i'm injecting co2 at a pressure of 35 psi

But are you rate limiting the CO2 injection? I mean I have my CO2 regulator set at 40 PSI but I don't have my needle valve opened up all the way. If you don't have a needle valve then yes you're probably gassing the fish.

 

[Nazdaq]

But are you rate limiting the CO2 injection? I mean I have my CO2 regulator set at 40 PSI but I don't have my needle valve opened up all the way. If you don't have a needle valve then yes you're probably gassing the fish.

Yes im using a needle valve, bubble counter maybe 3 bubbles per second, but this is not an accurate measurement of how much gets dissolved.

 

[dnL337]

i think one bubble a sec is what you want. Also, you need to have it turn off with the lights. Use a timmer

 

[Nazdaq]

i think one bubble a sec is what you want. Also, you need to have it turn off with the lights. Use a timmer

I am using a timer, but as i said the dropchecker was green, should it not be far yellow if it's too much?

 

[Bandit1200]

The color of the drop checker is greatly influenced by the solution you put in it. Was it a calibrated 4dkh solution?

 

[Nazdaq]

The color of the drop checker is greatly influenced by the solution you put in it. Was it a calibrated 4dkh solution?

tried the one i got from jbl and some other premixed i got from co2art. They both show about the same color, although one of them are a bit clearer

 

[cobra]

I once gassed 3 baby Starlight Plecos (and I am veteran with CO2). Have to be careful with this method! Do you know your water hardness numbers?

 

[Nazdaq]

it is a very soft water, below 3 according to test sticks

 

[cobra]

Yep, super soft water and using pressurized CO2 warrants extra care.

Use a calculator such as this in conjunction with your dropper:

Aquarium CO2 Calculator

 

[Nazdaq]

pH was 7.3 after lights off for 12 hours. So if it was 6.0 yesterday the co2 was probably more than 30 ppm. Gonna dial it to about 6.4 or 6.3 and see what happens. Say i have a kh of 2, then i had 60 ppm yesterday. Was trying to find info on cardinal tetra co2 sensitivity but the answers varied.