Drop checker & DIYCO2

[cbwmn]

Hello all,
I just want to relay an experience that I had a couple of months ago.
I have a 46 gallon bowfront with 6 DD black super veil tail angels in it.
I have a DIY 96 Watt A&H kit, DIY CO2 using two one gallon heavy duty bottles.
One morning I awoke and the angels were on their sides and swimming in loops. I immediatel did a huge water change and put an airstone in the tank (I have an XP 2 filter)
The fish came back and are now as healthy as ever.
I wrote a post similar to this one and was told in no way can you OD livestock with DIY CO2. I was also advised not to calculate the CO2 using KH/PH but buy DC’s instead.
I bought two Chinese drop checkers on EBAY and some 4dKH solution.
Hooked it all up and yesterday the solution was yellow. I loosened the cap on one of the tandem bottles and now the solution is finally in the green area.

Please don't let an “expert” tell you that you cannot OD your fish with DIY CO2. I know better.
I am going to remove one bottle now.
Charles

 

[fort384]

Charles,

Rather than removing 1 bottle, I would first try running an airstone at night (set it up on a timer opposite to your lights). This will allow you to keep the CO2 dosage up, but gas off the extra that can tend to build up when the lights are off. If you are still getting too much, then consider changing 1 or both bottles to a slightly smaller size and use a lighter mixture.

The reason is this: with 2 bottles, you can stagger the mixture changes, and keep the CO2 levels more consistent. If you go to 1 bottle, the mix will be strong in the beginning, and taper off before you have to change, lowering the co2 levels. This usually will lead to an outbreak in BBA.

I had a similar experience with my DIY system before adding the night time airstone. I checked by pH/KH in the AM after noticing my drop checker was yellow the next morning after adding the second bottle, and CO2 concentration jumped up to over 100 ppm. After adding the airstone, my co2 stayed at 30-50 consistently, morning, noon, and night.

Anyway, just food for thought.

 

[cbwmn]

Fort
I hadn't thought about the staggered CO2 mix. I still have an air pump and and airstone behind the tank. For awhile, I was just manually plugging it in at night. But without a drop checker, I really wasn't sure that's what happened to the fish. I have so many cords behind the tank now.

I'm thinking about using a valve from the CO2 line and just manually open it at night and vent to the outside. Since it took the tank 20+ hours to drop back to green, I don't think I'll lose that much CO2 saturation.
I have a DIY wooden hood with two 12 volt DC fans which require a power supply on an electronic timer. Plus the XP 2 is on a seperate circuit.
I'm really happy with the DC's, they take all of the guesswork out of the CO2 saturation.
Charles

BTW: When your solution is green what is the saturation range of CO2. I read it once but forgot where.

 

[fort384]

at 4 dKH it will be ~30ppm. Venting should work great too. I just liked the airstone because it was automated.

Of course, it might be a fun DIY project to integrate an electric solenoid so that it automatically vents at night, and closes during the day