Questions about drill holes

Greetings everyone, I just picked up a used ebb and flow system and I have a few questions as this is my first time without soil. I appreciate all the useful replies in advance.

Basically, I know there are supposed to be 2 holes (1 for fill, 1 for drain) but this system only came with 1 in the table and 1 on the side of the reservoir. Does this mean I need to drill another hole? This stuff is all used, so I'm baffled as to how the previous owner used it with just a fill hole. It's a botanicare system if that means anything.

Please take a look at the pics so you can see what I see and hopefully aid me in making sense of it... Thanks

i have never done ebb and flow but I'm guessing he just pumped it to a certain level then let the water drain back through the pump.

like i said just a guess

Thanks for the reply, I think I'm going to drill in the middle of it and put the fill plug there.

The blue tube is to provide you with a visual of how much water is in your res. If you drill a hole where you suggested in the pic, you'd a nice "drain & drain" table. I assume your friend probably trusted his cycle timing, but I'd still add an overflow port for safe measure against user error. Or keep that shop-vac handy.

Mike Young said:

The blue tube is to provide you with a visual of how much water is in your res. If you drill a hole where you suggested in the pic, you'd a nice "drain & drain" table. I assume your friend probably trusted his cycle timing, but I'd still add an overflow port for safe measure against user error. Or keep that shop-vac handy.

Click to expand...

Thanks for the reply, but when I said middle, I meant in the middle of the table... So, what I'm going to do is make the hole you just saw the drain side, and then I'm going to drill a new hole in the middle of the table for my fill plug and I'll attach that to the pump inside of the reservoir.