Plumbing help

[jeffberg]

I am setting up a new 300 gallon reef ready tank with overflows in back 2 corners. I have 1 1/2" stand pipes for drain water to the sump. The problem is the siphon will not restart in the over flows if I unplug the tank or worse the electric goes out like yesterday. The return pump runs dry before the overflows start to siphon back to the fuge. I have a 125 RR and it has always worked fine; what am I not seeing? Thanks Jeff

 

[nylogger]

You could put a low water cut off switch on your pump to prevent it from burning up if you power does go out. I have never liked siphon systems for that very reason. Would drilling the tank and adding an overflow system be an option?

 

[jeffberg]

I have never had a problem with siphon in my 150 which has over flow boxes or my 125 which is RR; they both fired right back up on the same power outage. where could I obtain this low water cut off switch? Thanks Jeff

 

[RBU1]

Not sure I follow what you are saying.Lets see if I have this right. Your tank has 2 overflows drilled with 1.5" drain lines and 1" returns...The overflow box's have teeth at the top correct? Is the 1.5" standpipe 1.5" the entire lenght or does it reduce when it hits the bulkhead? You have a hole in the top off the standpipe correct?

What exactly happens when you lose power? When the water is coming out of the sump back to the tank does the water in the tank get high enought to go thru the teeth in the overflow?

Also keep in mind that if you have your water return lines low in the tank the siphon will not break until it hits that spot.

 

[jeffberg]

I have 2 -11/2" drains draining to the sump; I have an hammerhead for return pump which is 11/2" too. I have the return flow going to 4- 3/4" Y locline fittings for tank circulation. The locline fittings are high enough in the tank and lines looped above them to create a siphon brake when the power shuts off and won't overflow my sump. When the power kicks back on the sump will drain before the standpipes start to siphon causing the return pump to cavitate. The standpipe is even with the top of the tank and I have a 1/4" adjustable valve in the top of the pipe. The return plumbing is about an inch and half from the bottom of the sump.

 

[RBU1]

OK I assume the water is going from your sump back to the tank. Is the level in the tank getting high enough to start the flow back in thru the teeth on the overflow box? If you want to call me 856-371-1090 I would be happy to try and help. I recently set up a 300. I am in NJ BILL

 

[mattsfishes84]

<a href=showthread.php?s=&postid=12252749#post12252749 target=_blank>Originally posted</a> by jeffberg
When the power kicks back on the sump will drain before the standpipes start to siphon causing the return pump to cavitate.

I think you mean "..standpipes start to drain.." rather than siphon.. if I understand you correctly.

But.. the problem may be in sump size. You see, upon startup the water level in the sump will go down significantly as the water is returned back to the tank. Then.. once it begins to drain again, the water level in the sump will stabilize. If your sump is not big enough to accommodate the water differential, then that may be causing your pump cavitation issue.

..if I understand your problem correctly. Pictures always help!