20 Best Diy Aquarium Co2 [2024]

Are you looking for the best diy aquarium co2? Based on expert reviews, we ranked them. We've listed our top-ranked picks, including the top-selling diy aquarium co2.

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1 Rhinox DIY Pressurized CO2 System, CO2 Generator Kit Includes Caps, Valves, 3-Way Connector, Tubing,... Rhinox DIY Pressurized CO2 System, CO2 Generator Kit Includes Caps, Valves, 3-Way Connector,...
2 Decdeal Aquarium DIY CO2 Generator System Kit with Solenoid Valve Bubble Counter Check Carbon... Decdeal Aquarium DIY CO2 Generator System Kit with Solenoid Valve Bubble Counter Check Carbon...
3 Wadoy Aquarium DIY CO2 Generator System with A Plug DIY CO2 Diffuser with Solenoid Valve Bubble... Wadoy Aquarium DIY CO2 Generator System with A Plug DIY CO2 Diffuser with Solenoid Valve Bubble...
4 The Little Green Change DIY CO2 Aquarium Plant System Kit - Generator Aquarium Moss Plant D201 Tube... The Little Green Change DIY CO2 Aquarium Plant System Kit - Generator Aquarium Moss Plant D201...
5 Clscea DIY CO2 Generator System Kit with Safety Valve 1 Second Quick Reaction for Aquarium Plants... Clscea DIY CO2 Generator System Kit with Safety Valve 1 Second Quick Reaction for Aquarium Plants...
6 FZONE 2.5L Aquarium CO2 Generator System Carbon Dioxide Reactor Kit with Regulator and Needle Valve... FZONE 2.5L Aquarium CO2 Generator System Carbon Dioxide Reactor Kit with Regulator and Needle...
7 Clscea G200 Aquarium DIY CO2 Generator System Kit Clscea G200 Aquarium DIY CO2 Generator System Kit
8 Neo CO2, Aquarium DIY add Co2 Diffuser Neo CO2, Aquarium DIY add Co2 Diffuser
9 Aquarium Choice 6 Pieces CO2 DIY Reactor Bottle Cap Fish Tank DIY Quick Twist co2 Bottle Cap with... Aquarium Choice 6 Pieces CO2 DIY Reactor Bottle Cap Fish Tank DIY Quick Twist co2 Bottle Cap with...
10 Clscea 2L Aquarium CO2 Cylinder Generator Kit CO2 System (Solenoid Version) Clscea 2L Aquarium CO2 Cylinder Generator Kit CO2 System (Solenoid Version)
11 DIY CO2 Generator System Kit with Pressure Gauge Air Flow Adjustment Valve - Pressurized CO2 Kit for... DIY CO2 Generator System Kit with Pressure Gauge Air Flow Adjustment Valve - Pressurized CO2 Kit...
12 Decdeal Aquarium DIY CO2 Generator System Kit CO2 Generator System with Solenoid Valve Bubble... Decdeal Aquarium DIY CO2 Generator System Kit CO2 Generator System with Solenoid Valve Bubble...
13 Yosoo DIY Aquarium Planted Tank CO2 System kit pro Tube Valve Guage Bottle D201 Yosoo DIY Aquarium Planted Tank CO2 System kit pro Tube Valve Guage Bottle D201
14 Hilitand CO2 Generator, DIY CO2 Aquarium Plant System Kit, D201 Pro Tube Valve Gauge Bottle Cap Kit,... Hilitand CO2 Generator, DIY CO2 Aquarium Plant System Kit, D201 Pro Tube Valve Gauge Bottle Cap...
15 Good news Aquarium CO2 Generator Carbon Dioxide Reactor Fish Tank DIY Quick Twist Bottle Cap Air... Good news Aquarium CO2 Generator Carbon Dioxide Reactor Fish Tank DIY Quick Twist Bottle Cap Air...
16 FZONE Aquarium Co2 Regulator DC Solenoid with Big Dual Gauge Display and Bubble Counter and Check... FZONE Aquarium Co2 Regulator DC Solenoid with Big Dual Gauge Display and Bubble Counter and Check...
17 FZONE DC CO2 Solenoid Valve Aquarium CO2 System Regulator Magnetic Valve for Aquarium Fish Tank... FZONE DC CO2 Solenoid Valve Aquarium CO2 System Regulator Magnetic Valve for Aquarium Fish Tank...
18 POPETPOP 2pcs CO2 DIY Reactor Bottle Cap Aquarium Carbon Dioxide Valve Guage Bottle Cap for Planted... POPETPOP 2pcs CO2 DIY Reactor Bottle Cap Aquarium Carbon Dioxide Valve Guage Bottle Cap for...
19 OIIKI 2 Pack Aquarium DIY CO2 Generator Bottle Cap, Carbon Dioxide Reactor, for Fish Tank, Aquarium... OIIKI 2 Pack Aquarium DIY CO2 Generator Bottle Cap, Carbon Dioxide Reactor, for Fish Tank,...
20 KUJOBUY DIY CO2 Generator Aquarium CO2 System kit pro Tube Valve Guage Bottle Cap D201 Cap for... KUJOBUY DIY CO2 Generator Aquarium CO2 System kit pro Tube Valve Guage Bottle Cap D201 Cap for...
SaleBestseller No. 1
Rhinox DIY Pressurized CO2 System, CO2 Generator Kit Includes Caps, Valves, 3-Way Connector, Tubing,...
  • Includes Equipment Needed To Do It Yourself --- In order to build an effective and efficient pressurized CO2 system, there are a few pieces of...
  • Generates Essential Co2 For A Healthy Habitat --- Fish and aquatic pets release cO2 when they take in the dissolved oxygen from the aquarium water and...
  • Cost-effective & Safe To Use --- Instead of spending hundreds of dollars on expensive CO2 diffuser set-ups, save money by creating your own...
  • Easy To Read, Specialized Pressure Gauge --- The SunGrow DIY CO2 Generator Set comes complete with a high-quality, specialized pressure gauge. The...
  • Create Homemade Drinks As An Added Bonus --- Obviously the DIY Pressurized CO2 Kit is designed to add and control the amount of CO2 available to your...
Bestseller No. 2
Decdeal Aquarium DIY CO2 Generator System Kit with Solenoid Valve Bubble Counter Check Carbon...
  • âœȘ【High-Quality Material】Be made of aluminum alloy. It is strong, durable and efficient. Well sealed caps and pipes, leak-proof, non-deformed,...
  • âœȘ【Solenoid valve】To control the on and off of CO2 generator system using with a timer(not included).
  • âœȘ【Bubble counter with check valve】Flow-rate of CO2 gas indication device and prevent water flow back into the bottle.
  • âœȘ【Equipped with a safety valve】The pressure is greater than 4kg pressure will relief automatically, carbonated beverage bottle pressure is 8kg,...
  • âœȘ【SATISFACTION GUARANTEE】If you are not completely satisfie, please contact us! We promise give a quick reponse and a nice solution. Choose us,...
Bestseller No. 3
Wadoy Aquarium DIY CO2 Generator System with A Plug DIY CO2 Diffuser with Solenoid Valve Bubble...
  • Packing Include:1 x CO2 System DIY Kit (Accessories: 1*Pressurized Gauge ,Full Set Air Hose , 1*Bubble Counter , 1*Suction Clips ,1*DIY CO2 Diffuser...
  • Well Designed: Simple to create pure CO2 constantly by chemical reactions. Full Copper Needle Valve,Professional Pressure Gauge.A Bubble Counter with...
  • Safty: Equappied with safty valve When The Pressure Is Greater than 4 kg, The Pressure Is Automatically Released. The Carbonated Beverage Bottle Can...
  • Multifunction : Add Citric Acid, Baking Soda, And Water to The Bottle to Produce Carbon Dioxide. This Allows The Plant Metabolic Rate to Increase...
  • We Gurarntee:For Any Reason You're Not Completely Satisfied, You Can Ask for A Replacement Or Full Refund.Just Use It with Confidence!
Bestseller No. 4
The Little Green Change DIY CO2 Aquarium Plant System Kit - Generator Aquarium Moss Plant D201 Tube...
  • â–ȘCO2 Generator:â–Ș AS an indispensable role in the photosynthesis of aquatic plants, this CO2 generator main for provides a genuine environment for...
  • â–ȘApplicationâ–Ș Easy to operate and designed for low cost planted tank use,to provide your aquarium plants an abundant CO2 environment for better...
  • â–ȘAdvantageâ–Ș This CO2 Generator System Kit is with Pressure gauge for pressure display, gas adjustable function, and simple pressure relief, easy...
  • â–ȘMaterialâ–Ș The CO2 DIY kit is with ABS engineering plastic cover, with a locking pipe device to ensure non-deformation, non-loose, non-slip wire...
  • â–ȘNote:â–Ș Make sure carefully observe the direction of the parts before assembly; The usual wrong handle way will cause abnormal reaction components...
Bestseller No. 5
Clscea DIY CO2 Generator System Kit with Safety Valve 1 Second Quick Reaction for Aquarium Plants...
  • The DIY CO2 Kit provides an excellent method of deploying the citric acid / baking soda solution to generate CO2 for plants' growing in the aquarium....
  • Highlight: A quick reaction test tube simplifies the procedure and achieves a fast reaction. 1 SECOND QUICK REACTION, works immediately, almost no...
  • Green body using high-quality PC material (bulletproof glass material), injection moulding. Extremely durable, corrosion-resistant, and not easily...
  • Equipped with a safety valve that automatically relieves pressure when exceeds 4 kg/cmÂČ, and it also supports manual adjustment. The magnetic acid...
  • Our CO2 Generator Kit includes most of the accessories. You only need to prepare yourself: 2 additional carbonated beverage bottles (preferably for...
SaleBestseller No. 6
FZONE 2.5L Aquarium CO2 Generator System Carbon Dioxide Reactor Kit with Regulator and Needle Valve...
  • Professional DIY kit. A complete system in 2.5L size bottle, that includes SUS304 stainless bottle, regulator, precision needle valve, and easy...
  • Safe. The bottle body is made of 1.5mm thick SUS304 stainless steel (25% thicker than normal 1.2mm bottle). It can sustain pressure up to 80kg/cm2(or...
  • Needle valve with bubble counter. High precision, aquarium specific needle valve provides accurate fine-tuning. Steady 1 bps is achievable. Bubble...
  • Optional:12V DC solenoid. Having the solenoid on a timer, you can specify when you want CO2 injection ON and for how long
  • Attentions. Solenoid NOT included, need order separately. Citric acid and sodium bicarbonate NOT included
Bestseller No. 7
Clscea G200 Aquarium DIY CO2 Generator System Kit
  • The DIY CO2 Kit provides an excellent method of deploying the citric acid / baking soda solution to generate CO2 for plants' growing in the aquarium....
  • Highlight: Much easier and safer to control. A quick reaction test tube simplifies the procedure and achieves a fast reaction. The unique design of...
  • Durable: Our tubing is highly resistant to pressure, and the tubing between the two caps is even acid- and hydrolysis-resistant. ABS engineering...
  • Our CO2 Generator Kit includes most accessories. You only need to prepare yourself: 2 additional carbonated beverage bottles (preferably for 2L), e.g....
  • All our products come with a WARRANTY! If there are any questions, suggestions or ideas, please feel free to contact us. 😊
Bestseller No. 9
Aquarium Choice 6 Pieces CO2 DIY Reactor Bottle Cap Fish Tank DIY Quick Twist co2 Bottle Cap with...
  • Aquarium Choice 6 pieces CO2 DIY reactor bottle cap Fish Tank DIY Quick Twist Bottle Cap with 118 INCH long hoses
  • Our product contains 6 pieces CO2 diy reactor bottle cap and 118 INCH long hoses.
  • The 6 pieces CO2 diy reactor bottle cap is made of high quality plastic material which will not create harmful material for fish and plant and the 118...
  • The 6 pieces co2 diy reactor bottle cap can be connected with the hoses with 4mm inner diameter and 6mm outer diameter
  • The 118 inch long hoses'inner diameter is 4mm and the outer diameter is 6mm.You can use the hoses to conncet to the co2 bottle cap and do not need to...
Bestseller No. 10
Clscea 2L Aquarium CO2 Cylinder Generator Kit CO2 System (Solenoid Version)
  • 【Support MORE raw materials】2.3L capacity and thickened wall cylinder, supporting 400g citric acid + 400g baking soda + 600ml water. Other...
  • 【304 stainless steel】Corrosion and high pressure resistant 304 stainless steel cylinder with a pressure load of 180kg/cmÂČ (2560 psi). Safer to...
  • 【High quality solenoid valve】The bubble counter is integrated with the solenoid valve and has a built-in check valve. And the solenoid bubble...
  • 【Attention】This set contains almost all the necessary accessories, only the reaction raw materials need to be prepared by yourself.
  • 【Most parts are replaceable】Quality inspection one by one, rather than random inspection! We are serious about quality control and buyer...
Bestseller No. 11
DIY CO2 Generator System Kit with Pressure Gauge Air Flow Adjustment Valve - Pressurized CO2 Kit for...
  • CO2 Generator: AS an indispensable role in the photosynthesis of aquatic plants, this CO2 aquarium kit for co2 diffuser for aquarium plants main for...
  • Application: Easy to operate & designed for low cost CO2 for planted tanks use, provide your moss and other plants an abundant environment for better...
  • Advantage: This CO2 reactor aquarium co2 kit is with pressure gauge for pressure display, gas adjustable function, and simple pressure relief, easy to...
  • Material: The DIY CO2 aquarium plant system is with ABS engineering plastic cover, with a locking pipe device to ensure non-deformation, non-loose,...
  • Note: Make sure carefully observe the direction of the parts before assembly of DIY CO2 kit for aquarium plants; The usual wrong handle way will cause...
Bestseller No. 12
Decdeal Aquarium DIY CO2 Generator System Kit CO2 Generator System with Solenoid Valve Bubble...
  • âœȘ【Be made of aluminum alloy】It is strong, durable and efficient. Well-sealed caps and pipes, leak-proof, non-deformed, never loose. Professional...
  • âœȘ【Solenoid valve】To control the on and off of CO2 generator system using with a timer(not included). Bubble counter with check valve: Flow-rate...
  • âœȘ【Equipped with a safety valve】The pressure is greater than 4kg pressure will relief automatically, carbonated beverage bottle pressure is 8kg,...
  • âœȘ【The safety valve supports manual pressure relief】When the pressure is below 4kg, it can be manually relieved by pull the ring of the safety...
  • âœȘ【Come with a bubble diffuser】Refine the bubbles and make it easy to dissolve in water and be absorbed by plants. Inject to your aquarium with...
SaleBestseller No. 13
Yosoo DIY Aquarium Planted Tank CO2 System kit pro Tube Valve Guage Bottle D201
  • you need to prepare following(not included): 2 x 2 Litre of Coka Cola plastic bottle, 1 x 200g of Citric acid or 200ml of vinegar, 1 x 200g of baking...
  • the bottle must be carbonated beverage bottle, do not use pulpy, green tea, mineral water bottles, etc.
  • trimming valve regulation avoid by sudden big or small, can't suddenly turn up, after immediately shut down again, so as not to cause abnormal...
  • Note: Make sure carefully observe the direction of the parts before assembly. The usual wrong handle way will cause abnormal reaction components as...
  • easy to set up
Bestseller No. 14
Hilitand CO2 Generator, DIY CO2 Aquarium Plant System Kit, D201 Pro Tube Valve Gauge Bottle Cap Kit,...
  • 【CO2 Generator System】As an indispensable role to the photosynthesis of water plants, this CO2 generator main for provide a real environment for...
  • 【Equipment Principle】The equipment uses an irreversible chemical of strong acid and strong base to produce CO2 gas. The pressure principle push...
  • 【Note】The bottle must be carbonated beverage bottle, do not use pulpy, green tea, mineral water bottles, etc.Trimming valve regulation avoid by...
  • 【Package List】Package includes 1 x Pressure gauge, 2 x Bottle Caps, 1 x Needle Valve and Tubes for easy installation, please make sure carefully...
  • 【Guarantee】If you have any quality problems, please feel free to contact us, we will provide you with a satisfactory solution, please feel free to...
Bestseller No. 15
Good news Aquarium CO2 Generator Carbon Dioxide Reactor Fish Tank DIY Quick Twist Bottle Cap Air...
  • The specification of the trachea that can be connected with the joint is 4MM in inner diameter and 6MM in outer diameter.
  • Reactor bottle cap to use on any soda/water bottle for a brine shrimp hatchery.
  • Use one side for the air pump, and the other side to release the brine shrimp into a container.
  • Add and control the amount of CO2 available to your fish and plants,add essential CO2 into your aquarium water.
SaleBestseller No. 16
FZONE Aquarium Co2 Regulator DC Solenoid with Big Dual Gauge Display and Bubble Counter and Check...
  • DUAL Big GAUGE! 1.6 inch big dual gauge easy to read your cylinder inner and working Pressure.
  • UPDATED SPLIT-TYPE DC SOLENOID! Newest 12 DC split-type solenoid instead AC models, more safe and stable. NEVER noise, automatic turn on/off CO2 with...
  • HIGH PRECISION STRUCTURE-This regulator is designed for the aquarium. High precision fine-tuning easy for co2 to be 1 bubble in 3 seconds. Upgraded...
  • BUBBLE COUNTER AND TOOLS INCLUDED! Together with bubble counter, you can read your co2 flow rate. Bubble counter with check valve function, stop water...
  • CLASS 1 MANUFACTURING TECHNOLOGY! Made of hard aluminum alloy, surface spraying treated. Pressure knob and fine tuning knob with knurl.
Bestseller No. 17
FZONE DC CO2 Solenoid Valve Aquarium CO2 System Regulator Magnetic Valve for Aquarium Fish Tank...
  • Upgrated 12V DC version. 12V DC powr input, Safer than AC input. Never buzzing noise( AC model long time using maybe have buzzing noise). Lower power...
  • Auto dosing co2 at the right time. Keeping your aquatic plants healthy doesn't have to cost a fortune thanks to this CO2 magnetic solenoid valve which...
  • Standard co2 6mm tubing fit. Fit for the 6mm pipe (inner diameter 4mm and outer diameter 6mm). Nuts locking design for CO2 pipe connection,...
  • Great partner for aquatic co2 system. It can be used for DIY aquatic CO2 system, and also can be used in CO2 tank system
  • Attention. Don't connect this solenoid to high pressure CO2 tank directly. it should be installed after the regulator, or used on DIY CO2 System. The...
Bestseller No. 18
POPETPOP 2pcs CO2 DIY Reactor Bottle Cap Aquarium Carbon Dioxide Valve Guage Bottle Cap for Planted...
  • Plastic material makes this bottle cap uneasy to rust and safe for your fish and water plant.
  • For people who love DIY CO2 setup, this bottle cap is a helper when they are doing the process of generating CO2.
  • Easy to use. Just screw the bottle cap on the drink bottle. Easy and sealed without letting the air out easily.
  • If the water plant in your fish tank/aquarium is growing slowly and needs more CO2, this bottle cap may help you.
  • This CO2 bottle cap is suitable for most kinds of DIY reactor.
Bestseller No. 19
OIIKI 2 Pack Aquarium DIY CO2 Generator Bottle Cap, Carbon Dioxide Reactor, for Fish Tank, Aquarium...
  • Size: Approx. 3.3x3cm(1.30x1.18inch); Material: Made of high quality plastic, very durable and can last a long life.
  • Features: Can be directly screwed to the carbonated beverage bottle to use,no air leakage, very durable and airtight.
  • Function: Can add or control the amount of CO2 which is available to your fish and plants, add essential CO2 into your aquarium water.
  • Application: Easy to install, and suitable for all kinds of DIY reactors.
  • After Sales Service: Any issues concerned after receiving or use, please contact us freely, we will try to issue you a reasonable solution. The...
Bestseller No. 20
KUJOBUY DIY CO2 Generator Aquarium CO2 System kit pro Tube Valve Guage Bottle Cap D201 Cap for...
  • The CO2 DIY kit is with ABS engineering plastic cover, with locking pipe device to ensure non-deformation, non-loose, non-slip wire when working.And...
  • According to the pressure principle,to push the acid liquid into the small soda liquid,the two liquids reacting to produce continuous PURE carbon...
  • This CO2 Generator System Kit is with Pressure gauge for pressure display,gas adjustable function,and simple pressure relief, easy to operate, safe...
  • Easy to operate and designed for low cost planted tank use,to provide your aquarium plants an abundant CO2 environment for better growing.

Having trouble finding a great diy aquarium co2?

This problem is well understood by us because we have gone through the entire diy aquarium co2 research process ourselves, which is why we have put together a comprehensive list of the best diy aquarium co2s available in the market today.

After hours of searching and using all the models on the market, we have found the best diy aquarium co2 for 2023. See our ranking below!

How Do You Buy The Best Diy Aquarium Co2?

Do you get stressed out thinking about shopping for a great diy aquarium co2? Do doubts keep creeping into your mind?

We understand, because we’ve already gone through the whole process of researching diy aquarium co2, which is why we have assembled a comprehensive list of the greatest diy aquarium co2 available in the current market. We’ve also come up with a list of questions that you probably have yourself.

John Harvards has done the best we can with our thoughts and recommendations, but it’s still crucial that you do thorough research on your own for diy aquarium co2 that you consider buying. Your questions might include the following:

  • Is it worth buying an diy aquarium co2?
  • What benefits are there with buying an diy aquarium co2?
  • What factors deserve consideration when shopping for an effective diy aquarium co2?
  • Why is it crucial to invest in any diy aquarium co2, much less the best one?
  • Which diy aquarium co2 are good in the current market?
  • Where can you find information like this about diy aquarium co2?

We’re convinced that you likely have far more questions than just these regarding diy aquarium co2, and the only real way to satisfy your need for knowledge is to get information from as many reputable online sources as you possibly can.

Potential sources can include buying guides for diy aquarium co2, rating websites, word-of-mouth testimonials, online forums, and product reviews. Thorough and mindful research is crucial to making sure you get your hands on the best-possible diy aquarium co2. Make sure that you are only using trustworthy and credible websites and sources.

John Harvards provides an diy aquarium co2 buying guide, and the information is totally objective and authentic. We employ both AI and big data in proofreading the collected information.

How did we create this buying guide? We did it using a custom-created selection of algorithms that lets us manifest a top-10 list of the best available diy aquarium co2 currently available on the market.

This technology we use to assemble our list depends on a variety of factors, including but not limited to the following:

  1. Brand Value: Every brand of diy aquarium co2 has a value all its own. Most brands offer some sort of unique selling proposition that’s supposed to bring something different to the table than their competitors.
  2. Features: What bells and whistles matter for an diy aquarium co2?
  3. Specifications: How powerful they are can be measured.
  4. Product Value: This simply is how much bang for the buck you get from your diy aquarium co2.
  5. Customer Ratings: Number ratings grade diy aquarium co2 objectively.
  6. Customer Reviews: Closely related to ratings, these paragraphs give you first-hand and detailed information from real-world users about their diy aquarium co2.
  7. Product Quality: You don’t always get what you pay for with an diy aquarium co2, sometimes less, and sometimes more.
  8. Product Reliability: How sturdy and durable an diy aquarium co2 is should be an indication of how long it will work out for you.

John Harvards always remembers that maintaining diy aquarium co2 information to stay current is a top priority, which is why we are constantly updating our websites. Learn more about us using online sources.

If you think that anything we present here regarding diy aquarium co2 is irrelevant, incorrect, misleading, or erroneous, then please let us know promptly!

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FAQ:

Q: How do you add CO2 to an aquarium?

A: Hemianthus Callitrichoides (HC) Cuba. Hemianthus Callitrichoides is more often sold as HC Cuba. … Rotala Rotundifolia. In contrast,Rotala Rotundifolia is a plant that can be used to good effect in the midground and foreground of the aquarium. Ludwigia sp. Red. … Alternanthera Reineckii. … Micranthemum Tweediei “Monte Carlo”. … Riccardia. …

Q: How to setup CO2 for aquarium?

A: CO2 bottle – CO2 bottles come in various different sizes. … Regulator – Carbon Dioxide is introduced firstly through the use of a CO2 regulator. … Solenoid – we love solenoids. … Bubble Counter – A bubble counter allows you to monitor the rate of CO2 entering your aquarium. … Diffuser – a diffuser allows an effective method for CO2 to enter the aquarium. …

Q: What are the best CO2 levels for an aquarium?

A: – Dark blue indicates a high pH/low CO2 (too little CO2) – Yellow indicates a low pH/high CO2 (too much CO2) – Green indicates the correct amount of CO2 for your plants, which is also safe for your fish

Q: How to make CO2 for planted aquarium tank DIY?

A: DIY CO2 in Planted Tanks. You can also insert CO2 into a tank using “do it yourself” methods (DIY). You can find most of the supplies needed to make a CO2 generator normally. First, grab two plastic bottles. You will want to drill a hole into the bottle cap of the bottle. You need a drill bit that is just a tad bit smaller than the CO2 …