Journal transitioning 75g to high energy

[sgheights]

After a couple years of disappointing plant growth as a low energy tank, I've decided to add CO2 and get serious. I'm a long time aquarist (20 years), but never CO2, so would appreciate help and feedback on my plan.

Current setup:
standard 75g marineland aquarium
fzone LED
biomaster thermo 350
corner matten filter driven by a DC pump
Sand
fertilization with APT3, Fe, K, fzone root tabs.

Fauna:

• Brutus, the royal acara Aequidens diadema
• An electric blue acara Andinoacara pulcher
• A T-bar cichlid Amatitlania sajica
• 5 melon barbs Haludaria fasciata

Flora:

• Windelov Java fern Microsorum pteropus
• Valisneria Americana
• Cryptocoryne wendtii
• Rotala sp.
• Amazon sword Echinodorus amazonicus
• Hygrophila angustifolia

Issues with the tank:

• cichlids love tearing up the plants and digging
• occasional bouts of cyano
• general poor growth of the plants (except for the Valisneria)

Plan:
add a yugang reactor inline with the filter.

• Aquarocks Colorado small acrylic yugang ($95) Yugang Horizontal CO2 Reactor - Acrylic
• 10lbs CO2 tank. (~$120 + $65 to fill) https://www.amazon.com/VEVOR-Aluminum-Cylinder-Adjustable-Dispensing/dp/B0DWMXPR8V?th=1
  • how much are people paying for CO2 tanks and refills? the only places near me charge $65+ to refill a 10 lbs tank.
• Regulator. undecided. Any suggestions?
  • Aquarocks Colorado ($160) ARC Premium Dual Stage CO2 Regulator
  • CO2Art ($150) https://www.co2art.us/collections/c...dual-stage-regulator-with-integrated-solenoid
  • Fzone ($136) https://fzaqua.com/products/fzone-pro-series-aquarium-co2-regulator
  • Archea ($110) https://aquaforestaquarium.com/coll...ual-gauge-co2-regulator-fits-cga-320-cylinder
  • others?
• CO2 tubing ($10) Silicone CO2 Tubing

How does this sound? anything I am missing?

 

[Koan]

Regulator. undecided. Any suggestions?

If the reactor is properly sized and set up to match the surface area of your tank, it will protect you from flaws in your regulator

That being said, for a few dollars more and a more durable option consider GLA: solid components lifetime warranty and great support

GLA PRO-DS-1 Dual Stage CO2 Regulator (Modular Manifold)

Dual stage CO2 regulator with modular manifold. Stable pressure, no end-of-tank dump, and expandable for multiple aquariums.

greenleafaquariums.com

GLA DS-Mini Dual Stage CO2 Regulator (Modular Manifold)

Compact dual stage CO2 regulator with modular manifold. Stable pressure, expandable up to 6 aquariums, and precision CO2 control.

greenleafaquariums.com

 

[BenB]

• 10lbs CO2 tank. (~$120 + $65 to fill) https://www.amazon.com/VEVOR-Aluminum-Cylinder-Adjustable-Dispensing/dp/B0DWMXPR8V?th=1
  • how much are people paying for CO2 tanks and refills? the only places near me charge $65+ to refill a 10 lbs tank.

First, the tanks expire. So most people get one from the gas company and swap it out every time rather than refilling it. I bought my first tank in '96 and it's never expired because I swap it out for a new one every time.

Secondly, I pay about that much for a 5lb. Its ridiculous. A 5lb will be fine for a 75gal tank for the plants you listed and most other plants in the hobby. But yeah, if you hope to get into more CO2 hog exotic things that down the road, a 10lb would be less hassle.

• Regulator. undecided. Any suggestions?

I agree with @Koan on GLA

• How does this sound? anything I am missing?

Backflow valve and a way to measure your CO2. Dennis Wong has a great article looking at different methods. HERE
Some of the more basic methods will work fine for the plants you have listed above, but like with the cylinder, if you decide down the road you want to get into CO2 hogs and fancy lights, the Hanna or Lamotte kits are the best.

Good Luck!

 

[Koan]

Backflow valve

Journal Post in thread 'Fishstery's Garden/Nature style hybrid'

Mar 3, 2026

push-in style check valves that also then serve as an easy disconnect

These are bulletproof

Mur-lok Inline Check Valve 1/4" x 1/4" Push Connect

Mur-lok RO fittings are the only RO fittings that feature dual EPDM O-rings to ensure a straight leak free fit. We believe GA Murdock Mur-lok fittings to be the best so strongly that we use them virtually exclusively on each of our BulkReefSupply.com reverse osmosis units and BRS media reactors...

www.bulkreefsupply.com

• Koan

• 

 

[sgheights]

Thanks for the advice! I'll go with a GLA reactor. Seems an important enough piece of equipment to spend $ on. And thanks for pointing out the check valve, I'll add one of those in.
The CO2 places in my area told me they also don't fill customer tanks, it's just a trade in, but it seems like buying a tank directly from them would be ridiculously more $ than amazon.

Thinking about how to arrange everything in the stand, do people secure their co2 tanks, or just let them freely stand up?

What's the current wisdom on drop checkers? useful or useless? I plan on using a Hanna co2 test kit to dial it in and for periodic checks, but would a drop checker be useful?

Finally, some photos of another tank: 60g cube. also no co2. AI prime FW. tetras, ricefish, apistos, corys. For some reason plants grow much better in here.

 

[BenB]

Thinking about how to arrange everything in the stand, do people secure their co2 tanks, or just let them freely stand up?

Mine sits in the stand, but I don't have children or pets.

What's the current wisdom on drop checkers? useful or useless?

There's pros and cons to all the methods. With a drop checker, you can be in trouble well before it ever turns yellow. I think most people get their CO2 set and then only check it periodically. It usually stays pretty stable. At least mine does. I get it though. If you're new to CO2, you might want to check it more often until you develop a comfort level. Look into the pH drop method. Also, I know this will get rocks thrown at me, yes I know it isn't super accurate, but I like the ph/KH table. In the old days, we used it over a decade before the drop checker was invented and even longer before the pH drop method was introduced. Either will get you by just to know you're not on the verge of gassing your fish.

Finally, some photos of another tank: 60g cube. also no co2. AI prime FW. tetras, ricefish, apistos, corys. For some reason plants grow much better in here.

Looks really nice. And again, with those plants, you don't need to put in a ton of CO2 to see big results. So you can work your way up to a goal level as your comfort, confidence, skills, etc improve.

 

[JayP]

Also, I know this will get rocks thrown at me, yes I know it isn't super accurate, but I like the ph/KH table.

Hmm, I know I have an extra piece of manten stone lying around.

 

[BenB]

Hmm, I know I have an extra piece of manten stone lying around.

Leave it to aquascapers to debate which would be the best type stone.

 

[Kwyet]

My CO2 tanks just sit under the stands. I guess it would make sense to secure them if they were out on the floor, but nothing will bother them under the stands.

I had drop checkers, got rid of them, and then put them back. I like the quick visual check that levels are as expected. They’ve definitely alerted me to unexpected issues like a skimmer getting clogged or a leak after replacing CO2.

 

[JayP]

I had drop checkers, got rid of them, and then put them back. I like the quick visual check that levels are as expected. They’ve definitely alerted me to unexpected issues like a skimmer getting clogged or a leak after replacing CO2

^^^^This!

 

[sgheights]

CO2 is set up and active!
Turned on at 3pm yesterday, with the reactor rotated to minimize the co2 bubble surface area, I tested 15-20 ppm after 2 hrs on.
timing: CO2 on at 9am, lights on at 11am. CO2 off at 8pm, lights off at 9pm.

I didn't use the mounting brackets built into the reactor, as they didn't work with my stand, and I wanted something more flexible for rotating the cylinder to adjust the CO2 levels. So I used 2 "6 Pack Heavy Duty Garage Hooks, Wall Mount J Hook for Hanging, Metal Utility Storage Hooks for Bike,Ladder, Hose". Just had to bend them a bit to fit around the reactor cylinder.

Some pictures of the tank and plants in their pre-CO2 condition.

Difficult to take a picture with a 2-door stand. Also I took this photo after the CO2 was off for the night.


Full tank shot. looks ok from a distance, but there's some neon cyano on the sand in the left, and poor plant growth overall. Also the monster, Brutus, who loves digging and tearing up plants.


unhappy rotala. val grows quickly, but algae grows on the leaves. Java ferns are doing well. Amazon sword hanging in there but grows very slowly. hard to take photos when the fish beg for food every time they see a human.



Crypts fairly healthy but algae on leaves.



Here's a list of all the components and prices involved in the CO2 system.

10lbs Co2 Tank	$65 (plus $100 tank deposit)
GLA GRO Aquarium CO2 Regulator	$125
GLA Aluminum Check Valve	$25
Aquarocks small acrylic Horizontal Reactor	$95
CO2 tubing	$10
drop checker	$10
j hooks (to hold reactor)	$26
OASE Biomaster Thermo 350 (already owned)	($310)
Hanna Co2 kit	$67
kasa timer	$10
total	$341 (651 with Oase filter)