Secret Jardin DF25250 Flange 250 mm

Ø 250 mm connector for the DF25 flange holder, the largest in the series. Meant for setups where the resistance of the air path has become more important than the fan itself.

Going wider without buying a bigger fan

Most growers do not need this size, which is a more honest starting point than pretending bigger is always better. There is one situation where it is the answer, and it has little to do with capacity.

A fan only delivers its rated flow against low back pressure. Every metre of ducting, every bend and every filter adds resistance, and that resistance climbs steeply with air velocity. If your air path gets long, or has many bends in it, a perfectly good fan suddenly delivers far less than its rating promises.

The answer then is not a stronger fan but a wider path. Move from Ø 200 to Ø 250 mm and the opening grows from roughly 314 to 491 cm², more than half as much again. The same volume of air travels through it more slowly, resistance falls, and your existing fan delivers more while making less noise.

Where you meet this: a long run to the outside, a setup with several bends, or a noise-sensitive room where you deliberately keep velocity low.

Technical Specifications:

• Connection diameter: Ø 250 mm
• Opening area: roughly 491 cm², about 56% more than Ø 200 mm
• Largest connector in the DF25 series
• For holder: DF25, Ø 25 mm poles
• Typical use: long duct runs, many bends, noise control
• Fixing: clips in, no tools needed
• Material: plastic
• Revision: R4.00

Frequently asked questions

Do I need a 250 mm fan for this?
No. You can step up from a smaller fan to a wider duct size through a transition. That is precisely the reason to choose this size.

Will my extraction get stronger?
Indirectly. The fan does not become more powerful, but it works against less resistance and therefore delivers more.

Is there anything larger?
Not within DF25. Above it Secret Jardin uses the separate DFM315 flange for Ø 315 mm.