Waste water help

I'm having trouble finding a way to deal with waste water that I like. Was hoping to get a good idea from someone. The closet is 6' long and I would eventually like to pipe it through the wall and into a drain.

Well there is a few options here that would do the trick, you could get some 5 gallon buckets and also some large netpots that fit onto them without a lid, which would allow you to add bulk head pipe fittings and some poly pipe connected to the buckets for drainage, would require your grow area to have access to a drain on the floor or you could buy some large rectangle storage tubs that fit your area and place plants inside this, along with a bulkhead fitting and poly pipe for a drain.

Hope this makes sense I have no pics

If I went with something like this water heater drain pan and tilted it at an angle would the little bit of water left in the pan be a problem?

Would be no problem at all as long as they are able to drink that excess water within 24 hours