If you are planning to grow in a small enclosure where heat could be an issue, it may be a wise choice to use an Ecotechnics Cooltube reflector to fit in line with your extraction system.
The design of the Ecotechnics Cooltube allows you to blow or extract air through the reflector and over your lamp, ensuring all the heat from the lamp is taken away before it can raise the temperature in your grow room. The Cooltube has a reflector inside the glass tube and there are also a set of reflector wings provided to ensure all the light is pushed downwards towards your plants. Hanging eyes are fitted and a 4 metre cable with an IEC connection is also fitted to the reflector to connect it straight to your HID ballast.
Cooltubes are a great reflector to use if you are using several lights in a large room or tent as they can be linked together with some ducting to allow you to run one large fan to extract the heat from them all.
Important
Never run your light with no extraction running through the Cooltube, as it will heat the glass quickly and may cause it to crack.