Several questions about DIY Co2

[PunkRotten]

Hello,


I am currently using a DIY Co2 on my 29 gallon. I get about 1 bubble every 2-3 seconds. I have a few questions/concerns, hopefully someone can help me out.


1. Is it advisable to shut off the Co2 after the lights are off? I am afraid of overdosing my fish with Co2. Should I just unscrew the cap on the bottle?


2. My tank is a low tech set up. I added the DIY Co2 to boost growth. Since the plants grow slower at a lower lights, does this mean that the Co2 will not be used up as good? Is any Co2 being wasted or is it kinda unnecessary to be using it in the first place?


3. Is 1 bubble every 2-3 seconds good? Sometimes I get 1 bubble a second. My biggest concern is the health of my fish. I want to stay away from any risk of them dying. What concerns should I have if any? And at what point would the health of the fish be at risk? What are signs of Co2 overdosing? Thx

 

[PunkRotten]

Anyone????

 

[pepetj]

You may find answers to your questions by searching the forum.

1. Ideally yes but doing it by unscrewing the cap will require some time after placing the cap on for internal pressure to build up so that the generator can push CO2 through the tubing; adding an airstone to inject bubbles of atmospheric air through an airpump controlled by a timer so it runs at lights off period prevents most respiratory problems for fish and inverts (lack of dissolved oxygen, too much dissolved CO2).

2. Unless you run a grossly overstocked tank dissolved CO2 would be low. It may work well depending on all the other variables involved. It's not the same to keep a "low light loving" plant that grows slowly in a low light tank with non-CO2 (e.g. a la Walstad) than attempting a plant that can grow in low light yet is known to be a fast grower in mid or bright light.

3. Bubbles per second don't account for good reliable measure but as to give us a rough idea of how our flow of CO2 into the reactor/diffuser is going; bubbles likely change in size from one DIY CO2 generator to the next as well as through the lifetime of a generator.

The level of dissolved CO2 is what we use to measure how our CO2 system are working. Drop checkers is the most used "instrument" to infer it (some have estimate its error of measurement as above 30%); using pH and KH test kits and a chart is another (likely with major errors of measurements), while using lab grade CO2 test kit (I use Hach) may provide reasonably reliable readings. A dissolved CO2 meter with probe is also in the market but at a prohibitive price for our purposes (around 8,000.00 USD).

Balancing a planted isn't a straight forward light:CO2 ratio; Macro and Micro nutrients, as well as temperature, pH and plant species also play an important role. To infer light intensity the WPG guideline is used, yet only with a photosynthetic photon flux meter (available at around 400USD) we can actually know how much light we have at substrate level, shadowed areas, etc.

Low tech tanks as well as high tech tanks and whatever set up that lies in the middle can be kept without measuring much variables. In the end careful constant observation tell us what we need to know: are plants growing as expected? is algae growth under control?

Pepetj
Santo Domingo