Cylinder choice begins with the role it must serve and the gas plan it must support. Our verified aluminium-cylinder coverage currently contains nine Catalina S-series models, so this guide does not add a tenth from a different product class. The table compares dimensions, service pressure and published buoyancy where available. Local approvals, inspection status and valve compatibility still need checking.
Updated · Manufacturer specifications and published review evidence
How we chose and ordered these picks
The familiar S80 leads, then smaller main-cylinder candidates and compact specialist sizes. Position is not a recommendation that a smaller cylinder meets a particular dive’s gas needs.
List position is an editorial recommendation, not a review score. The selection uses the documented features and limitations below. We have not personally tested this equipment. Verified publisher scores, where available, are shown separately and link to their evidence. Our catalogue is still being researched; inclusion does not mean a product has a completed scored review.
The shortlist at a glance
Choose a model to jump to its details. Compare the exact configuration before ordering.
Catalina’s S80 is an aluminium scuba cylinder with 11.1 litres of internal water capacity and a 207 bar working pressure. Despite the familiar “80” name, Catalina lists 77.4 cubic feet of air capacity. Its broad 184.2 mm diameter and 14.2 kg cylinder weight matter when checking harness fit, transport and handling.
Material
6061 aluminium
Water capacity
11.1 L
Air capacity
77.4 cu ft / 2192 L
Service pressure
3000 psi / 207 bar
Dimensions
184.2 mm diameter × 658 mm cylinder length
Cylinder weight
14.2 kg
Listed buoyancy
-1.6 lb full; +2.8 lb at 500 psi; +4.1 lb empty
What to check
The manufacturer lists buoyancy changing from -1.6 lb full to +2.8 lb at 500 psi. Account for that change in the complete rig rather than treating it as a fixed ballast contribution. Confirm the actual valve, cylinder markings and local filling acceptance before purchase. Social Diving’s pressure and height figures differ from Catalina’s cylinder table; the manufacturer values are used here.
Published review score: 96/100★★★★★★★★★★4.80/51 rated publisher group(s) · not the position in this list
S63 is Catalina’s shorter alternative to the familiar S80 format. The official specification sheet gives 9.0 litres of water capacity and 63 cu ft air capacity in a 551 mm cylinder. Its 184.2 mm diameter matches S80, but its listed weight is lower at 12.2 kg.
Water / air capacity
9.0 L / 63 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
184.2 × 551 mm
Cylinder weight
12.2 kg
Buoyancy: full / 500 psi / empty
-2.8 / 0.7 / 1.8 lb
What to check
The product page ambiguously lists water capacity as “11.1, 9”; the manufacturer’s specification sheet identifies S63 as 9.0 litres. Its buoyancy reaches +1.8 lb empty. Check the valve and total rig rather than treating a shorter cylinder as a direct substitute for the larger supply.
No verified independent overall score yet. Compare the specifications and limitations above.
S53 is a 7.6-litre aluminium cylinder with 53 cu ft of air capacity. Its 184.2 mm diameter matches S63 and S80, but the body is only 488 mm long. Catalina lists 11.4 kg, making this a short cylinder rather than an especially light one.
Water / air capacity
7.6 L / 53 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
184.2 × 488 mm
Cylinder weight
11.4 kg
Buoyancy: full / 500 psi / empty
-3.8 / -0.8 / 0.1 lb
What to check
The listed buoyancy is -3.8 lb full, -0.8 lb at 500 psi and +0.1 lb empty. Compare those figures with the regulator-equipped rig you will use. Older third-party charts list different weights and buoyancies; they should not override the current manufacturer table.
No verified independent overall score yet. Compare the specifications and limitations above.
Exact-model photo not yet verified. See the manufacturer specifications for dimensions.
S50 provides 50 cu ft of air in a 7.2-litre aluminium cylinder. Its 175 mm diameter matches S45, while the 493 mm body adds capacity with a listed weight of 9.9 kg. It is narrower than the S53 despite their similar overall size.
Water / air capacity
7.2 L / 50 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
175 × 493 mm
Cylinder weight
9.9 kg
Buoyancy: full / 500 psi / empty
-2.4 / 0.4 / 1.2 lb
What to check
The specified buoyancy becomes positive near the end of the fill: +0.4 lb at 500 psi and +1.2 lb empty. Valve and rigging choices alter the assembly. The manufacturer page has no verified exact-model photo, so a logo is no longer shown as the product.
No verified independent overall score yet. Compare the specifications and limitations above.
Exact-model photo not yet verified. See the manufacturer specifications for dimensions.
S45 is a short, relatively broad aluminium cylinder with 6.4 litres of water capacity and 45 cu ft of air capacity. Its 450 mm length is useful to compare against taller cylinders, while the 175 mm diameter and 9.2 kg weight prevent it being mistaken for a narrow stage bottle.
Water / air capacity
6.4 L / 45 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
175 × 450 mm
Cylinder weight
9.2 kg
Buoyancy: full / 500 psi / empty
-2.8 / -0.3 / 0.5 lb
What to check
Catalina lists buoyancy moving from -2.8 lb full to +0.5 lb empty. The official page currently supplies a placeholder rather than an exact product photo; the previously assigned logo has been removed. Check local supply and valve options directly.
No verified independent overall score yet. Compare the specifications and limitations above.
Exact-model photo not yet verified. See the manufacturer specifications for dimensions.
The S40 is Catalina’s narrower 5.8-litre aluminium scuba cylinder, with a listed air capacity of 40 cubic feet at 207 bar. At 133.4 mm diameter and 645 mm cylinder length, it has very different proportions from an S80. Its size can be useful for a separately rigged cylinder where the required gas volume has been established.
Material
6061 aluminium
Water capacity
5.8 L
Air capacity
40 cu ft / 1132 L
Service pressure
3000 psi / 207 bar
Dimensions
133.4 mm diameter × 645 mm length
Cylinder weight
7.3 kg
Listed buoyancy
-1.5 lb full; +0.7 lb at 500 psi; +1.4 lb empty
What to check
Catalina lists a 7.3 kg cylinder weight and buoyancy of -1.5 lb full, rising to +0.7 lb at 500 psi. Valve, regulator and rigging affect the assembled result. A smaller cylinder is not automatically adequate as an emergency supply; capacity must come from the dive plan. Confirm markings and acceptance with the filling provider.
No verified independent overall score yet. Compare the specifications and limitations above.
S30 combines 30 cu ft air capacity with a 4.3-litre internal volume. At 133.4 mm across and 505 mm long, it sits between Catalina’s narrow S19 and longer S40. The listed 6.2 kg cylinder weight makes transport and mounting more substantial than its compact capacity suggests.
Water / air capacity
4.3 L / 30 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
133.4 × 505 mm
Cylinder weight
6.2 kg
Buoyancy: full / 500 psi / empty
-2.4 / -0.7 / -0.2 lb
What to check
Catalina lists -2.4 lb buoyancy full and -0.2 lb empty. Treat these as cylinder specifications, not a weighting prescription for an assembled system. Verify the actual valve, markings and inspection history before choosing a used example.
No verified independent overall score yet. Compare the specifications and limitations above.
S19 holds 19 cu ft of air in a 2.7-litre aluminium cylinder. Its 111.3 mm diameter matches the smaller S13, but the 450 mm length gives it a noticeably taller profile. Catalina lists 3.5 kg before adding the rest of a breathing assembly.
Water / air capacity
2.7 L / 19 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
111.3 × 450 mm
Cylinder weight
3.5 kg
Buoyancy: full / 500 psi / empty
-1.5 / -0.4 / -0.2 lb
What to check
The manufacturer’s buoyancy table remains slightly negative when empty. Check the complete rig rather than assuming the cylinder figure includes your valve, regulator and clips. Its capacity must follow a gas plan, not a generic “pony bottle” recommendation.
No verified independent overall score yet. Compare the specifications and limitations above.
S13 is Catalina’s short, narrow aluminium cylinder: 1.9 litres of water capacity in a 325 mm body. The 13 cu ft air capacity and 2.6 kg cylinder weight make it a compact option when a separately planned small gas supply is required.
Water / air capacity
1.9 L / 13 cu ft
Service pressure
3000 psi / 207 bar
Diameter × cylinder length
111.3 × 325 mm
Cylinder weight
2.6 kg
Buoyancy: full / 500 psi / empty
-1.8 / -1 / -0.9 lb
What to check
Catalina lists the bare cylinder as negatively buoyant even when empty. That does not establish the buoyancy of a regulator-equipped assembly. A compact bottle is not automatically an adequate bailout supply; capacity, valve and local filling acceptance must suit the intended configuration.
No verified independent overall score yet. Compare the specifications and limitations above.
Product research checked 2026-10-03. Specifications can change; confirm the exact model and package.
Before you buy
Use your gas plan and training to establish capacity requirements.
Check local cylinder approval, markings and inspection requirements.
Match the valve, regulator connection and mounting system to the actual cylinder.
Take two or three suitable models from this list into a comparison, then remove any that fail your fit or compatibility checks. A lower position here can still be the better purchase for your setup. Check the product page for source dates and unresolved details before placing an order.
Does the model number equal water capacity in litres?
No. These S-series numbers refer to nominal gas-capacity classes. The specifications separately list water capacity and rated gas capacity.
