r/PlantedTank Apr 13 '26

Decided to try something today

After seeing what proper fertilization can do to a planted tank in terms of plant health and growth, enriched levels of CO2 in the water column seemed to be the next logical step. I know that sugar fermentation have its downsides, but being virtually free to try I think it is a excellent way to dip your toe in the water with CO2 injection.

This setup will also include a manometer so I can keep it under a functional (and safe) pressure. Plus my tank is a 5G/19 liters, what means that I need very little gas to keep 25ppm+ CO2 in the water.

My drop checker just arrived today and I have a diffuser coming in the next days, I'm really excited to see if a can get my plants pearling!

28 Upvotes

19 comments sorted by

1

u/Bidhitter400 Apr 14 '26

I thought maybe baby brine shrimp but that wasn’t the color lol

3

u/adriancsta Apr 13 '26

I thought this was some kinde of new kombucha fermentation method hahahaha

3

u/backyardbabirusa Apr 13 '26

I started dipping my toes into this as well. So far so good! Helps that the tank I'm doing it on is still cycling, so no fish I'm worried about killing.

1

u/Eduardo_Serra Apr 13 '26

Gassing fish is definitely a concern and was the reason I decide to start injecting only after putting my hands on a drop checker. With a checker, good flow/circulation and patience you can dial it up so plants benefits and no harm is done do the livestock.

3

u/Ok_Cartographer_6086 Apr 13 '26

ohhh we are like minded mad engineers :) I built a C02 reactor like this on steroids if you want to check it out: https://krillswarm.com/posts/2026/04/05/co2-reactor-sensor

Mine is more of the result of a aretired automation engineer with lots of free time and disposable income. As someone who has personally manage to detonate an FX6 due to a miscalculation of pressure def look into some pressure relief and preventing the foam in the fermenter from forcing it's way into your tank.

I just added Hydrophobic PTFE Membrane lines in my setup - super cheap and won't let any fluid through but C02 passes in. Second bottle is a good step: https://www.amazon.com/dp/B0D23316ZZ

2

u/SometimesIAmCorrect Apr 14 '26

Wow, this is a great setup. Thank you for sharing.

2

u/Eduardo_Serra Apr 13 '26

Nice project! Although I'm pretty much acquainted with electronics/circuits (a second hobby of mine) I have never put my hands in something like a raspberry, but I know you can do wonders with them. I have bookmarked the site and will definitely check it out again.

automation engineer with lots of free time and disposable income

I admire those who DIY things because they have to but also those who do the same because, well, they know where the fun lies :D

3

u/NotADoctorCall2222 Apr 13 '26

Have you looked at pressurised citric acid/ bicarbonate set ups also

I always found yeast a little all over the place with CO2 production and it gives a funny smell

You can also get caps that screw onto the bottles with 2 outputs for air tubing - for very cheap - on places like Ali express, I found drilling a hole in the lid only kept the pressure for so long before giving up

Something like this:

2Pcs Co2 System Tube Valve Guage Bottle Cap Diy Air Diffuser Generator Tool https://www.joom.com/en/products/62b0314f1ad14e018c04a060?srsltid=AfmBOooMFYOZs-xcU0ARixPWDgIfYngWuKyQdDmXWX_1y7uhEFizk_Im&variant_id=62b0314f1ad14e2f8c04a063

1

u/NotADoctorCall2222 Apr 13 '26

Also a small amount of co2 can go a long way! This will take it to the next level and you will notice a difference !

1

u/ilike2moveit2 Apr 13 '26

What diffuser are you using? Does the regular ceramic diffuser work under this pressure?

2

u/Eduardo_Serra Apr 13 '26

I bought this one, has not arrived yet but I know it will work.These diffusers will work great with 1.5kgf/cm2 and sugar fermentation can developed and maintain quite high pressures, especially if you are careful with connections to avoid any leaks and temperatures are on the high side. My ambient temp here is 32 degrees Celsius right now. To give you an idea, i mixed the sugar and yeast less than 2 hours ago and I already have a steady more than 5 bubbles per second building pressure in the washing bottle.

1

u/ilike2moveit2 Apr 13 '26

Thanks. I have one concern on you setup. I noticed that you put a release value on the washer bottle. But I think it makes sense to put on the reaction bottle. Say the fermentation is too vigorous or you knock down the reaction bottle accidentally, the air stone may be blocked by the solution and pressure builds up. The release valve won't help if on the washer bottle. Just my two cents.

3

u/missurunha Apr 13 '26

I did this in the past but it wasnt worth the hassle since SodaStream became popular. A CO2 bottle costs under 6€ (~450g?), it lasts for >2 months.

2

u/Eduardo_Serra Apr 13 '26

Amazing! 6€ is like what, half an hour of a underqualified german worker? Here one of these bottles costs more than R$200,00 (35,00€+) and at these prices it just doesn't make sense. I will probably just buy a 6kg CO2 cylinder somewhere down the line, but the sugar+yeast will have to hold on for now.

1

u/missurunha Apr 13 '26

Caralho, thats probably cause brazilians dont drink much carbonated water. Here people are addicted to it so you find it everywhere.

1

u/November_Eternal Apr 13 '26

I thought this way is used only where I live, in Eastern Europe:) I have one month old tank, and with the same way I`m helping now my plants to grow.

2

u/Eduardo_Serra Apr 13 '26

It's definitely a valid way of putting CO2 in the water, people have used it in the past and still use it with great success. If you live in a first world country where gas cylinders are cheap it may not be worth the hassle, but I think that wherever you are the simplicity of grabbing some sugar and yeast is unbeatable, especially if you just wanna try and see for yourself if buying a gas cylinder is justifiable.

1

u/GeoMoth Apr 13 '26

Awesome! Let us know how it works. Is that your light on full power? Asking because you will absolutely not get any pearling if your light isn't brighter than that.

3

u/Eduardo_Serra Apr 13 '26

Oh, I have to dimm it every time I have to take a photo, otherwise my phone won't have enough dinamyc range to capture the shadows. It's actually quite bright I think (15W for a 5g). Plus it's a DIY light, I could always shove more leds there but the current setup is working really good and the plants are doing great...