i've got one and baffled it myself. Get the black drainage tubing from B&Q was about £30, cut in into sections and just feed it into the top of your tank, job done!
Tony
Here's the thread from when I asked for advice :
Re: Ordering WFP kit today, Any advice?
« Reply #12 on: October 17, 2009, 11:29:24 AM »
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Tony,
Following on from Matts advice about unbaffled tanks.
Buy 25m of 100mm land drain from a local builders merchants should cost you about £35, cut it into 4 lengths of approx 6m each then just feed them into the tank ( dont worry about which way they go in as they will coil up naturally ).
It will take you about 20 minutes and then you have a good cheap baffled tank.
Regards