[esloq]

I am new to this, so: Hi everyone. I did keep some fish as a kid, but that was a long time ago.

My question is:

Has anyone been successful in having a CO2 injected 2.5 gallon shrimp planted tank? Without, of course, killing all the shrimp.

As my come back to the hobby I started a 2.5 gallon tank about 4 months ago, it is well cycled, heated and with an AquaClear filter. I have a few Dwarf Shrimp living in it.

The thank is made up of:

• UNS Controsoil, river pebbles, and sand as a substrate
• Dragon Stone (hardscape)
• Vallisneria Spiralis (background)
• Java Moss (foreground)
• Salvinia Cucullata (floating)
• Anubias Nana and a Marimo Ball

My plan is to start injecting CO2 into this.

I've built a pH controller that measures and stores pH levels every 5 minutes.

I haven't started CO2 injection, instead I've been just watching the normal pH cycle up and down and recording the data:

The idea is to learn what the normal parameters are for this tank, and then, once I have a good idea of what cut off values should be use those to shut off the CO2 if the pH drops below normal.

Thanks, and any tips for successful micro CO2 injected will be greatly appreciated!

 

[massinelli]

Hello there!

Well, my (short) experience with nano tanks, co2 and shrimps (i have a 7gal with some rcs and a pair of rams) tells me that is possible to inject co2 without killing the habitants. But you have to be extremely cautious about the co2 levels over time, since it reaches its limits very quickly. I suggest you to buy a drop checker and whenever you turn on the co2 keep your eye on the solution colour. Considering that takes some time to the solution to changes its colour, i also suggest that you turn on the co2 and turn it off after 30min, wait some time (30-40 minutes more) and see if the solution turns green, if still blue, turn the co2 on for more 30min and repeat the process until its green. After you get that deep green colour i recommend to turn off the co2. You'll get how much time it needs to be on to achieve the perfect levels.
I think a low bps rate like 1bp5s would be great.
It can be more demanding, since you'll need to keep an eye constantly, but it pay its price.
By the way, its really nice what you did with the ph monitor!

 

[Scully]

Personally, unless you're planning on adding more demanding plants I don't see a point in adding CO2 to your tank. Those are all low-tech plants that don't require CO2, if you have a nice equilibrium in your tank now I wouldn't change it up.

 

[a modest aquarist]

I agree with Scully here, unless you're wanted to add co2 as an experiment or using the tank to collect data. Stability is key and as you may already know, it's harder to achieve the smaller the tank. So if it's just satisfy your curiosity, I would rather use the fancy pH controller for an experiment with a larger tank.

That being said though, I personally would be interested in your findings. I'll continue without knowing what your experience with co2 is like. pH fluctuates all the time, but with co2 many aquarist aim for that peak 30ppm during their photoperiod and in smaller tanks you hit that fairly quickly in my experience (running co2 in a 5 gal). Not quite sure on what you mean by "micro injecting" but let me share some data points with you. My water has a pH of 7.4 out the faucet and to achieve 30ppm of co2 I have hit a pH of 6.4 (referring to kh/ph charts on the forum). For my 90L (21 gal) about 4 bub/sec, and in my 7 gal cube 2 bub/sec and about 1 bub/sec in my nano 5 gallon. I use mostly lower light plants with some medium light ones so that will be a factor in addition to varying substrates, driftwood, and other things that affect pH. My assumption is that you'll be in the 1 bubble per second or even 1 bub/2 sec range for a 2.5 gallon but of course YMMV.

If you do add co2 please keep us posted. I'd like to see the data/chart collected. I imagine it's going to be all over the place since you're only dealing with 2.5 gallons of water and because it'll continue to change over time as the substrate loses the ability to buffer, plant growth, etc. Honestly, I don't think you'll see a big return on using co2 especially with your existing plants, but nevertheless still very interesting.

 

[esloq]

If you do add co2 please keep us posted. I'd like to see the data/chart collected. I imagine it's going to be all over the place since you're only dealing with 2.5 gallons of water and because it'll continue to change over time as the substrate loses the ability to buffer, plant growth, etc. Honestly, I don't think you'll see a big return on using co2 especially with your existing plants, but nevertheless still very interesting.

Yes, thanks for the comments, this is mostly an experiment (but still do not wish to see dead shrimp). My goal is to learn a bit more about CO2: see how it changes and what are limits in a 2.5 gallon. Also to learn about the reliability and accuracy about the hardware I'm making. Then, maybe in a year, I'll get a larger tank (~50 gals.) and move the CO2 paraphernalia no that new larger tank.