Help tuning reef tank ASAP PLZ!

[EpicVegas]

I have a 55 gallon reef tank with a 20 gallon sump. I have the 55 gallon tank filled up about 95% with the waterline just under my drain and over flow box.

My question is how do I balance the drain and return?
I have a gate valve on the drain and return.
My sump is also filled about 65% of the way.

What is my next step??
I don't want to flood anything lol

[sslak]

You shouldn't have to balance the drain and return.

Your return pump should pump slightly slower GPH than your drain is capable of. Example: if you have a 700gph drain, you should buy a pump that will do less than 700gph after you figure in head loss.

That way, the pump can never out-run the drain.

Once you start everything up, figure out your sump level. There should only be one chamber where the water level fluctuates- that's the one with the return pump. How full you keep it is up to you, but you should have enough water to cover the pump + at least 2 days worth of evaporation.

- If you're not sure about the gph of drain and pump...turn it on and see what happens. Just watch the water level in the overflow box..it should not rise up to the point that it's even with the water in the display. If it does...it's probably not draining fast enough and be ready to shut it off so it doesn't flood.

If your pump is too powerful for your drain, you can throttle it back...but that's not recommended for most pumps as it will cause extra wear and tear.

[EpicVegas]

Good info I just have one more question. Do I need a syphen broke drilled into my return inside the tank? It's a 90 PVC elbow thats turned sideways. I also have a one way valve in my return line.

Also how does a syphen brake work?
Thanks

[Bender19]

Yes, you should have a hole drilled in the return line slightly under the water line to break your siphon. It allows air to enter when the water level drops below it and breaks the siphon. As for the one way valve. Never rely on it, when you need it the most is when it breaks :)