Overflow/drain pipe help!!

So I finally have my 80 gallon tank up and running stocked with just live rock. @ weeks ago when I tested the flow of my tank with just tap water, making sure everything ran good and no leaks, it ran great on the first try. The only problem was my drain pipe to my sump was a little loud because the first row of holes that I drilled was about an inch over the water line. So I made a new drain pipe lowered the holes so that they are all submerged but now the overflow is gurgling and the pump is faster than the flow. I know this because the water level in the sump is down an inch and the level in the DT is up. Please let me know if you have any ideas for a fix.

Thanks

J

 

Is this an external or internal overflow?

 

external, Eshopps PF-800 and using a Mag 7 for return

 

Do you have the internal box in the tank? I had a similar issue when I first setup my first HOB overflow.. and I forgot to add the little box that regulates in the DT.
Added it.. then no issues at all... it will only gargle now when the pump is catching up with the overflow.

 

I know I have the overflow installed correctly because a couple of weeks ago on my test run of the system it was working great. I guess I got greedy when trying to silence my drain pipe because that is the only thing that I tinkered with between then and now. Same number of holes in the drain pipe, same size, only difference is now all of the holes are submerged versus the old pipe had a row of 3 holes that was above the water line. Would this be the difference in my flow?

 

You need to dial down the flow. A gate valve is ideal, ball valve will work but not as well, and either needs to be placed after the pump on the return line.

 

^^^^ bingo!!!!!

 

I guess I am trying to figure out why it is doing this now and not 2 weeks ago. I used simple plumbing then and my tank ran great. No air in the siphon and I dont know why its gurgling.

 

How long did you run the system two weeks ago? It can take a while before the gurgling starts.
The gurgling is happening because the pump is returning the water to the tank faster than the overflows will naturally allow. So it is creating a forced vertex/siphon. That is why you always should install a gate valve on the output of the pump in order to dial it down a bit as needed.

 

I ran it for 3 days