Thank you for your post and interest in Drs. Foster & Smith. The IceCap Double Ended Socket # CD-14782 150 watt that you are inquiring about will not support 400 watts. We apologize at this time we do not have a double ended ballast in stock that can support the 400 watts you are looking for. However, we are constantly expanding our inventory and recommend that you check our website occasionally.
We apologize for any inconvenience this may have caused you. If we can be of any additional assistance, feel free to contact our Live Aquaria Department at 1-800-334-3699 or via email at [email protected]
and we will be happy to answer any question(s) you may have.
Drs. Foster & Smith