JCO - You mentioned changing the direction of the water. I think I have done that to some degree in the past. For example, instead of it just pouring straight into the grow bed, I attached a 90 degree elbow and extended the output to another area of the tank. If I ever want to change directions, I simply can twist this pipe 180 degrees, and wallah: it will now be on the opposite side of the tank.

Of course, like you mentioned, that doesn't really CLEAN anything, so eventually I will have to clean the grow beds.

But I guess back to my original question: Are there any recommendations on how you would clean out a grow bed that has established plants in there? I just struggle with how to do it and not completely destroy some of the plants. I guess it's going to be somewhat of a compromise: if you want to keep perennial plants, you have to be willing to sacrifice the ability to easily clean the grow bed. Correct?

Thanks for all the help. If I have time, I will post a youtube video just to show what my two year old system looks like.