Plumbing Pro's, A little Help Please...


New member
Looking for a little help with fitting sizes for my drain line fittings. What I want, they don't sell around here, so I have to order online and I am not sure of the sizes and what not.
I have an AGA 90gl Mega flow. I think the predrilled holes are 1inch drain and 3/4inch return.

I want to use the herbie method on this so I need new bulk heads that have slip fittings. would it be slip on slip? 1 inch and 3/4in correct? I will need the basic pvc pipes for inside the box, I guess there 1 inch right and 3/4 ? Could I make the pipe 1 inch and reduce to 3/4, or is that pointless.
Then under the stand I need to drain with pvc but I need a gate valve and I am not sure of the size.

I have to order this online, so I want to get it right so I do not have to return anything.

Thanks for the help.


New member
The Megaflow holes are 1 inch and 3/4 inch. In my tank, I used slip x slip bullkheads. Threaded vs slip is really a personal preference. Advantage of threaded is that you can unscrew the plumbing from it if needed without cutting the pipe. Disadvantage is that since they are not glued, there is the chance of water leaking through the threads. I went with slip x slip for this reason. You can always add in unions so that you can take apart the plumbing if needed.

Yes, you will need a 1 inch bulkhead and a 3/4 inch bulkhead. The PVC pipes you'll need are 1 inch and 3/4 inch as well. I would leave it with a 1" drain all the way and 3/4 return all the way-- no need to reduce anything in my opinion. With the gate valve being on the drain with 1 inch piping, you will need a 1 inch gate valve.