I got burnt by CO2~!

Yep, end of tank dump, wondered why I was having trouble getting the diffusers to act right. One larger tanks , I often check the gas level, but on the smaller set up I have not changed it for 2 years now and figured it might be the tubing etc, but nope.

Then no gas came out today and I knew it was something else right away.

So if you think you are an expert, it really does not matter, the hobby will always make you think twice and rethink thing and be more humble.
At least I can take my own advice and know I can rule most things
It's just the things that you do not think about that will get you.

Regards,
Tom Barr

It's happened to Amano more times than you know.

Regards,
Tom Barr

No fish losses, I've actually never lost a fish to CO2.
Gassed a few good in the past, but they all lived.

Amano has killed many fish with CO2. He freely admits it.
pH controller got some at least once in his case.
Same deal with me but I caught it first and tossed the pH controller after that and will never use one again.

Generally the end of tank dumps apply to non needle valved systems.
Dave Gomberg use tio suggest a needle valve was not needed and sold Ehiem diffusers and reg's with no needle valve. Folks did fine till they got near the end of the tank and needle valve acted as choke to reduce the variation, but without one, many folks lost their entire livestocks due to this.
Dave's killed more fish with CO2 than many.

But now we know and adding a needle vale in conjuction solves the death issue with fish, but we still have a lower and lower CO2 rate and less CO2 in the start of lighting cycle, so it's a problem, but with plant growth and algae instead of dead fish.

I can get rid of algae and bring plant growth back, I cannot reainmate fish

Regards,
Tom Barr

Ideally most throttle the pH controller to match the use by the tank.
That way if the solenoid sticks open, they do not gas their fish, but then the trade off is slow response times to depletion.

There is always a trade off.
The one I do not like: high CO2 at night.

If I have high CO2 during the day, it's off set by high O2 levels from the plants.
Not so at night time.

Chronic high CO2 cannot be a as good as a daily spike along with a spike of O2.
Just because the CO2 at night does not kill the fish, it remains to be seen if it's not bad for them as well over the long term. Few looks at the sublethal effects of toxicants at higher levels.

I'm a CO2 conservative today, but at one point, I was adding more than most anyone.

I add a lot only during rh day, the control is a needle valve which is very easy to adjust. More plant biomass as the tank grows, the more CO2 demand and the more gas I add.

You can set the pH controller fraction, the switch plug in, and add a lighting timer there. That way the pH controller only added CO2 during the day and maintains it.

pH probes can fall out of the tank.
The elctrical solenoid or unit can break etc.

Needle valves are cheap and reliable overall.
Like a Regulator/gas tank.
pH controller is an added expense that certainly no one needs, I do not think it gains anyone an adavtange, but seem to assuem that it does because they sell you on "automated CO2, pH stability and control" and 100+ $ later, you try and find some value yourself

I do use a pH monitor, they(controllers) are good for that, but not exactly portable tank to tank really. The control function is the needle valve and the solenoid that turns on for 10 hours a day.

Those tend to be pretty reliable.
Fish can certainly be fine and okay in both cases, but you know less CO2 at night has to be better for the fish...........and with all the whining and carrying on folks do about excess NO3's etc............I find it odd they have no issues adding lots of CO2, Amano is certainly guilty of this.

the real question that remains unanswered is what are the sublethal effects over time on fish/shrimps etc.

I see ADA's tanks and I really wonder why they have such few fish, a very commmon comment by many, and I cannot help but think they all got gassed.

The tanks I have are either test tanks and I do not have any fish, or they are packed in general.

I liked fish before I got into plants, one does not replace the other, they complement the other.

Some place plants primary or fish primary.
I focus on both.

Regards,
Tom Barr