Cloudray S4, AC Infinity, Grow Tent Clip Fan, 10 Speeds, 100 mm (4 Inch)

The Cloudray S4 is the compact end of AC Infinity's clip fan range — a 4-inch (10.2 cm) circulator built for propagation tents, cupboards and small grows where a 6-inch fan simply won't fit, or where it would eat canopy space you can't spare. It's also the natural choice for the lower position in a two-fan setup, where you want a targeted stream through the stems and base. It uses a high static pressure design to push a tighter, faster column of air than its size suggests, and it's the quietest fan in the Cloudray line at 29 dBA. You still get the full feature set: 10 digital speeds, 10 dynamic wind modes, 10-level automatic oscillation, IP54 weatherproofing and UIS™ connectivity.

How much airflow, and where to point it

A circulation fan isn't a per-plant purchase, and the number of plants isn't the right way to size it. What you're aiming for is simpler: everything in the space should be moving slightly, all the time. Leaves should have a gentle, constant flutter — not being whipped around, and not standing dead still. Still air is where problems start; violent air causes its own.

Height matters as much as coverage. Air moving across the top of the canopy does nothing for what's underneath it, and the lower growth and the base are exactly where stagnant, humid air settles. The setup that works best in most spaces is two fans at different heights: one above or across the canopy, and a second lower down aimed through the stems and the base, so air is moving right through the plant rather than just over it.

The S4 is well suited to that lower position. Its tighter, faster column of air reaches through dense lower growth where a wide soft spread would stall, and its narrow body fits low down without crowding the space. That's a more useful rule than a fan-per-plant count — set them to a speed where the whole space has movement, check the corners and the lower growth, and adjust from there.

Tailored, custom airflow

10 speed levels, 10 dynamic wind modes and 10 oscillation settings give you precise control at every stage of growth — from ultra-gentle airflow for germination and seedlings through to firm circulation for mature plants. In practice: run it low and steady for young plants so stems strengthen without stressing them, then step up speed and oscillation as the canopy fills out. The 90° rotation range with 55° tilt lets it work around lights, ducting and trellis netting rather than being blocked by them.

Nothing is cut down to hit the smaller size. The S4 has the same speed range, the same wind modes and the same automatic oscillation as the 6-inch and 9-inch Cloudrays — it's a smaller impeller, not a stripped-back model.

Compact engineering

The S4 pairs a miniaturised EC motor with a high static pressure design, which is what lets a small impeller still throw air across a space. At maximum speed it generates a higher wind velocity than the larger Cloudrays do — it moves less total volume, but it moves it faster and in a tighter column. That's the right trade in a confined space, where a wide soft spread just bounces off the walls.

The S4 stands about the same height on a tent pole as the 6-inch S6 — 24.9 cm against 24.7 cm — but it's 21.6 cm wide against the S6's 30.0 cm, near enough 8 cm narrower. Width is the dimension that matters inside a tent. A 4-inch head clears lights, ducting and trellis netting that a 6-inch head fouls, and casts far less shadow across the canopy.

Cabling is generous for a fan this size. The power supply sits inline on the cord rather than being a separate item to keep track of: 10 ft (304.8 cm) from the fan down to it, then a further 8 ft (243.8 cm) to the wall — around 5.5 m of total reach, so you can site the fan high in the tent and still land the plug outside it.

Construction matches the rest of the range: brushless motor, carbon steel gears, and dual-ball bearings that AC Infinity rate at 67,000 hours of continuous operation, plus an IP54 rating so humidity and the occasional wipe-down won't kill it. Power draw is 11 W. The space-saving metal clamp uses a vice-grip-style mechanism, so it holds position on tent poles instead of drooping over a cycle.

Full specifications

FAQ

How many fans do I need?

Judge it by movement rather than by a count. Everything in the space should be gently moving; if anything is standing still, you need more airflow or better placement. In practice most spaces want two fans at different heights — one across the canopy and one lower through the stems and base — rather than one fan working harder. The S4 is a good fit for that lower position, and for small spaces it can do the whole job on its own.

Where should I position it?

Not aimed straight at the plants at close range. Low down, point it through the stems and around the base so air moves under the canopy rather than just over it. Up high, aim slightly above or across the canopy so the air rolls through the space instead of blasting one spot. Oscillation spreads the same airflow across a wider area rather than hammering one point.

The S4 and S6 are the same price — why would I take the smaller one?

Straight answer: if you have room for the S6 and it's your only fan, take the S6. The S4 earns its place in two situations. First, where a 6-inch head won't fit or would block light — small tents, cupboards, wardrobe setups, shelves. It stands the same height on the pole but is 21.6 cm wide against the S6's 30.0 cm, about 8 cm narrower. Second, as the lower fan in a two-fan setup, where a tighter, faster stream through the stems is exactly what you want. It's also the quietest of the three at 29 dBA. Buy it for the fit, the placement and the noise floor, not to save money — there's no saving to be had.

Is 204 CFM enough for my space?

One S4 handles a 2×2 comfortably and will do a 2×4 if you position it to work with your extraction airflow rather than against it. It's also the right fan for the Cloudlab Advance Propagation Tent (60 × 60 × 90 cm) and similar propagation spaces — at 21.6 cm wide it leaves you working room, where a 30 cm S6 would take up half the width. In a larger space, use it as the lower fan alongside an S6 or S9 above rather than expecting it to cover everything alone.

Do I need a controller to use it?

No. It plugs straight into a wall outlet and runs on its own controls with 10 speeds, 10 wind modes and 10 oscillation levels. Connecting it to a UIS-compatible AC Infinity controller adds app control, scheduling and climate-triggered automation, but isn't required.

How quiet is it really?

29 dBA at maximum speed, and quieter still at the mid settings most people use — that's below the level of a quiet room, and the lowest rating in the Cloudray range (the S6 is 31 dBA, the S9 is 35). If noise is the constraint driving your setup, this is the clip fan to pick.

Can I leave it running 24/7?

Yes — and you generally should. Air should be moving continuously, not in bursts. The EC motor and dual-ball bearings are built for continuous duty, the IP54 rating handles humidity, and at 11 W it's among the cheapest things in a space to leave on.

Will it fit my grow tent's poles?

Yes — the clamp uses a vice-grip-style mechanism designed for round tent poles and mounts horizontally or vertically, so it can go wherever you need airflow and holds firm even on poles that have worn or bent slightly over time.

Is this a genuine AC Infinity unit with Australian warranty?

Yes. Quick Bloom Lights is the official Australian importer and distributor for AC Infinity. Every unit ships with a fitted Australian three-pin plug — no travel adapters, no rewiring — and a two-year warranty handled here in Sydney, so there's no shipping units overseas and no dealing with an offshore seller if something goes wrong.

I'm not a grower — is this any good for other uses?

Yes. It was designed for growers, but plenty of ours end up on desks, in offices, workshops, server cupboards and caravans. The appeal is identical either way: 29 dBA makes it the quietest fan we sell, 11 W means it costs almost nothing to leave running, and the clamp fixes it to a desk edge, shelf or bedhead instead of taking up floor space. Of the three Cloudrays it's the best desk fan — smallest footprint, lowest noise, and a directed stream rather than a room-wide draught.