Climate & Ventilation — Ø 250 mm

Ø 250 mm is room scale rather than tent scale: several tents on one extraction system, or a properly fitted grow room. It is also the top of what is stocked here, and that changes how you buy. At the smaller sizes you assemble a chain from parts that match; at this size you are mostly adapting.

Parts are the largest group here, and that follows

At this scale it is rare for everything to run on one diameter. You step down to a smaller filter size, split a run to two spaces, or connect to what is already installed. The reducers go from 250 back to 200, 160 and 125, and T-pieces, Y-pieces and bends all come in this size. Count those parts into your pressure loss rather than treating them as an afterthought.

Fans: Vents has the widest choice here

The Vents VK 250 comes in several versions and the TT Pro 250 as a mixed-flow, with the AC Infinity CLOUDLINE Pro S10 at the top of that range. The Can-Fan Iso-Max 250 at 1480 cubic metres per hour is the pre-damped option, and the exception within its own family: it has a single fixed speed and is the only Iso-Max that may take a speed controller.

At this flow rate noise is the real problem

The more air you move, the louder everything gets: the fan, the air in the duct and the vibration through your structure. Alongside the Iso-Max there is a 50 cm silencer in this size, and acoustic Sonoconnect and Sonodec also come in Ø250. Over a long run, acoustic duct often does more than a single silencer at the end.

This is where the range stops

Nothing above this size is stocked. If you run something larger, the reducer to 250 mm is how you get a carbon filter onto it, because the largest filter connects at Ø250.

Frequently asked questions

Can I step down from 250 to a smaller filter?
You can and people often do, but it costs pressure and the filter saturates sooner, because more air passes per square centimetre of carbon. Only step down when a matched filter is not possible.

Is one large extraction better than two small ones?
For several tents in one space usually yes, because you buy one filter and one silencer. If you want to control each tent separately, two smaller systems are more practical.

Why is the fan choice narrower here than at 125?
Because the range follows what people grow. The middle sizes are the most common and therefore have the deepest choice; this size is more specialised.