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Availability:
In Stock.
Arrives
Saturday, Feb 28
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Color: G802S
Features
- 4L large capacityOnce fill, longer use, suitable for medium or large plant tank.
- Right out of the boxNo need to purchase reactants, this kit contains the complete ingredients for one reaction.
- Triple Stainless Steel Filter Element Minimize the failure of solenoid valve.
- 304 Stainless Steel The bottle, regulator and the filter element are all made of high quality 304 stainless steel, more safe and durable.
- Convenient & Worriless 1 second quick plug high quality solenoid valve and bubble counter, low temperature and quiet.
- Filling tips: If you have a kitchen scale, you can add the recommended amount according the bottle neck sticker. If you don't have one, please just put 3A3B reactants which come with the kit and 900 ml water. Both filling methods are safe and feasible.
Brand: Clscea
Liquid Volume: 4 Liters
Item Form: Liquid
Manufacturer: Clscea
Package Dimensions : 16.14 x 12.52 x 5.87 inches; 9.66 Pounds
Date First Available : March 11, 2021
Manufacturer : Clscea
Best Sellers Rank: #50,960 in Pet Supplies (See Top 100 in Pet Supplies) #181 in Aquarium Air Pump Accessories
#181 in Aquarium Air Pump Accessories:
Customer Reviews: 4.3 4.3 out of 5 stars (285)
Item Weight: 9.64 pounds
Manufacturer: Clscea
Date First Available: March 11, 2021
Item Package Dimensions L x W x H: 16.14 x 12.52 x 5.87 inches
Brand Name: Clscea
Target Audience Keyword: Fish
Directions: Fill the bottle with 900 ml of water and the 3A3B reactants that come with the kit. If you have a kitchen scale, you can add the recommended amount according to the bottle neck sticker. The kit contains complete ingredients for one reaction, so there's no need to purchase reactants separately. The product should be used with a 304 stainless steel bottle, regulator, and filter element to ensure safety and durability. The solenoid valve and bubble counter are convenient to use and operate at low temperatures and quietly.
Color: G802S
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Saturday, Feb 28
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Top Amazon Reviews
UPDATE: After buying the Clscea co2 system I came across another “mini” system from Chihiros Aqua which looked high quality so out of curiosity I purchased it to compare. After using both systems for a few days my original 5-star review is validated. The Clscea system blew it out of the water. The Clscea regulator is much easier to dial-in and maintain its setting whereas the Chihiros regulator would constantly change and in some cases completely stop the flow of co2. If you want a budget co2 system it doesn’t get better than the Clscea. I’ve been in the nature aquarium hobby for quite some time and have used CO2 systems that cost quadruple this price. I was very hesitant to try a “DIY” CO2 kit since all of my previous systems were pressurized, but that said, I decided to try this out because my nano tank is only 2g and I didn’t want to spend hundreds of dollars on a CO2 system. When I received the kit I was surprised with the quality the canister and most of the components - the biggest downside is the included diffuser which is made of cheap plastic. While the diffuser does work, I would definitely recommend buying a higher quality diffuser and one sized for your tank. Set-up was really easy however I wish Clscea included a scoop for the ingredients instead of simply instructing you to use "grams". I took another reviewers advice and used a 1/4 cup however I don't think that measurement is entirely accurate so I'd recommend using a coffee scale if you have one. Overall everything went smoothly - just remember to install the inner filter first before screwing on the regulator. Now that I've had the system running for a few days I will say I'm incredibly impressed with how easy it was to set-up and the quality of the solenoid and regulator. Because my tank is so small I needed a really precise regulator to get to ~5-6 bubbles per second and I had zero issues achieving that with this kit. I also have the solenoid on a timer and it works perfectly without any change to the regulator setting after turning back on. Overall I highly recommend this kit (so far) as long as the solenoid doesn't require maintenance too often, that's really the only potential downside. Good news is Clscea does sell parts on Amazon in case you need too replace it. But OOTB for the price I definitely recommend giving this a try.
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Reviewed in the United States on August 1, 2024 by Mad Mensch Mad Mensch
This CO2 system is amazing. I did not realize how small the tank was but it is more than adequate for my 26 Gallon bowfront planted tank. At 1 drop per second which is perfect for this tank (I have C02 indicator in tank) the plants are growing like crazy. All the included parts work perfectly. I did switch over to a thicker CO2 tubing but initially ran it with the included tubing which worked perfectly. Although the adjustment know is sensitive it is not an issue to set it exactly how you want it and it stays put. Lasts 10-12 days before I have to refill with Clcitric acid & baking soda but it uses so little of both that it is extremely cost effective. It does not come with the citric acid or baking soda but I purchased big bags of each on Amazon for dirt cheap. I highly recommend. You can't beat the system for the price. Although a bigger tank would last longer, this is perfect because I can hide the tank behind my stand.
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Reviewed in the United States on September 10, 2023 by David B David B
I didn't have high expectations for this item, having come from a paintball CO2 system years ago. This thing is fantastic for the price, although I do wish the diffuser was glass instead of plastic, that's a small nitpick as it works perfectly. Everything else, from the canister, gauge, needle valve and solenoid are high quality, and I expect them to last awhile. I was up and running within 1/2 an hour, from unboxing to finish. Strongly recommend the 1.3l system for a nano tank - mine is a 5 gal and this is perfect for it. This deserves a higher overall rating than it has. Update: bought the biggest CO2 tank they sell for my wife and her 210 gal freshwater setup. Absolutely thrilled her - works perfectly and lasts her about a month per recharge, even running two solenoids. Excellent value for the price and highly recommended.
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Reviewed in the United States on February 23, 2025 by J. Brown
Color: G802S
I am a Failure Analysis Systems Engineer for the Department of Defense and felt an assessment would be helpful for any potential buyer.. I have the G802S for my 40 gal aquarium and have it running for 4 days now. This unit generally is impressive for the price. However, there are a few things you may want to know... First, the Pros... 1) Overall build quality is good for the price. 2) The tank, fittings, and documentation are all good generally. 3) The regulator and solenoid valve are both working properly. 4) The needle valve is easy to adjust, and the provided tubing length with suction cups is adequate for most purposes. Now, the Cons... 1) The weakest issue with this kit is the hard tubing where it enters the diffuser chamber that releases the gas as fine -bubbles into the tank.. See the attached photos. The rigid tubing leaks where the tubing enters the bottom half of the diffuser chamber. The vendor's associated YouTube video warms against mishandling this connection during diffuser stone replacement., which clearly indicates they know about this weakness and expects you to adapt. However, in this case, the diffuser was already assembled when I attempted to use it and yet is was leaking upon initial testing. I tried to get e replacement of just this one small part with Amazon Customer Service (neither Customer Service nor I couldn't find any direct contact info for the vendor), but Amazon stated the only remedy was to return the entire system for replacement or a refund. They do have a website at clscea[dot]net... Good luck with that... Another online video on YOUTUBE also mentioned this weakness and recommended using the NEO CO2 diffuser instead, as well as replacing the backflow check valve with a more sturdy metal version. I used the CLSCEA plastic valve and it appears to work properly so this is your choice . The Amazon cost for the NEO diffuser was $21.00 at time this writing this. I must say, this is a good option, and appears to be much better in overall design than the provided CLSCEA version. Again, see the attached photos. The white diffuser is the CLSCEA version. Note the bubbles leaking off to the left of the chamber from underneath. The brown diffuser stone is the NEO unit, which does a better job with dispensing the bubbles. I recommend this for anyone considering this product, although it adds $20 to the overall investment. 2) You may want to use a timer switch to controller the power to the solenoid. You only need the CO2 flow during the daylight hours and to run it 24 hours per day will waste your gas. Another $10 or so but less headaches... 3) The pressure gauge is very small and is somewhat difficult to read. A large face would be better. In summary, this product is on the verge of being a really good one. The vendor just needs a better diffuser solution. Good luck!
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Reviewed in the United States on February 8, 2026 by Jimbo Jimbo