What is going on with my pump/closed loop?

[tleilaxu]

I followed Melev's diy closed loop (only exception was without the wavemaker and with 1" pvc rigid and flex) for my 72 gal tank. I'm using a GenX-4100 Submersible Pump
1085 GPH
9.2ft maximum lift
UL approved
Ceramic Shaft, adjustable flow
1 year guarantee against manufacturer defects.
PSI Rating 3.98
5/8" and 1" ID Hose fittings included.
750 gallons at 3' Head
650 gallons at 5' Head

This is 3ft under the tank. When we first turned on the pump I got a nice stirring up, lots of circulation, there were bubbles but not for long. A few hours later I checked the water pressure coming out and it had considerably slowed down.

I thought there might be a working in period and things would go back to the way it was when we first turned it on.

But tonight not only am I not getting any better circulation (water pressure against my hand in front of the outlet) but my tank temp has gone up 3 degrees. I'm running this externally, but I do have it in a container holding water (did this to test & see if it would help muffle the sound) so I don't understand why I'm getting such a high temp change from an external pump and at the same time I'm hardly getting any pressure coming out/circulation.
This is set up for a softie/lps tank so I didn't want too much pressure. Would I necessarily feel that much pressure coming out? I am not seeing the swirling about that was going on before though!!

Has anyone had issues with this pump? The pump is not exactly flat, would this play into this? Could this pump be defective?

 

[countertopguy]

What size plumbing are you using?

 

[miztic]

because it's a closed loop, the head pressure shouldn't matter at all, it sounds to me like something is clogging up the tubing or the impeller.

 

[Jon Evans]

I agree, it is probably your impeller

 

[melev]

I believe your pump is starving for water. Using flexible hose, you have to use hose barbs. These have smaller ID, acting as a restriction.

If you can increase the plumbing going into the pump, I have a feeling you'll get more flow and the pump's temperature will drop.

 

[john rochon]

flex hose, I believe she means flex PVC. no hose narbs there.

 

[tleilaxu]

Thanks for all your help guys. I'll ask my husband what it's called but the flexible tubing to the pump is clear with what looks like criss-crosses in it, technically I don't think it's considered pvc (should have pointed this out before). He's running this for about 1.5 feet into the pump and again out, I didn't have much room under the tank to play with so we needed to have something that was flexible.

It seems to be the same diameter as the rigid tubing (it's running over the pvc fitting that is attached to the 1" tubing) and he used clamps (just in case) to keep it in place (although I doubt it would ever come off). I've seen people here using that stuff and I'm using that clear tubing in my overflow as well.

I was trying to figure out exactly where there problem could be and I think another factor may be that I have to lift the tubes out of the tank slighly more, I'm not getting a lot of surface aggitation which is making me wonder if perhaps that has a card to play in all of this. (heat issue anyhow not the pressure coming out)

Although the depth of the pipes may play in the heat issue, it wouldn't explain the circulation issue. I'm no plumber by any means and I wasn't quite sure if I would feel that much pressure coming out but from your responses I guess I should be feeling (seeing) more than what I'm getting.

So should I turn this off and pull the pump apart to see if the impeller is jammed? What could it possibly be jammed with? It was running for maybe an hour when I noticed the flow issue, and it's hardly like anything large enough could have gotten sucked into it.

I should also point out that I used a piece of pvc and drilled holes as in the instructions but my piece of pvc with the holes in it is about 9-10" , I'm not feeling super suction (nothing swimming outside is going to worry about getting sucked in) so I don't think the pump is being starved for water there.!?

 

[keeperofthefish]

The heat is most likely a result of the pump, which is water-cooled and is therefore quite likely to add a few degrees to a tank. Hate to say it, but you'd be better off with an external pump--especially since you have no need to run it submerged. The PanWorld line would make an excellent choice.

 

[tleilaxu]

I understand what you're saying about the pump but when we set it up we were nervous about noise so we put the pump in a holding container with water. The pump is not warm and neither is the water in the container.

I didn't take into account that the pump would be giving off heat so I didn't adjust the heater, which is now adjusted.

 

[countertopguy]

<a href=showthread.php?s=&postid=6745074#post6745074 target=_blank>Originally posted</a> by melev
I believe your pump is starving for water. Using flexible hose, you have to use hose barbs. These have smaller ID, acting as a restriction.

If you can increase the plumbing going into the pump, I have a feeling you'll get more flow and the pump's temperature will drop.

This is what I was getting at with my comment about the size of your plumbing. I had a similar situation. My CL pump ran hot and made a lot of noise until I increased the size of the intake plumbing. I now have no noticable increase in temperature and no excessive noise.


Steve

 

[rustybucket145]

Sounds like you have a blockage somewhere in your system. I would start by taking apart the loop. You may have to cut it and couple it back together. I had the same problem with a skimmer. One day it was fine the next day it was barely putting out any water pressure at all. I thought my pump had gone out. I took the skimmer apart and unscrewed all the barbed fittings that were on the system. Low and Behold two tiny pieces of coral/shell had somehow made it past my strainer and into the system. They each were small enough to fit through the pipe fittings but it seems they tried to pass at the same time and became lodged in the pipe. This greatly restricted my water flow and caused my pump (external) to put off more heat than normal. So before you go and buy a new pump check to be sure you have nothing blocking your flow.

 

[j0tca]

For 1050 GPH, 1" piping, even the re-inforced vinyl tube that you're using, will have a great enough ID. Your impeller is jamed, or their is something blocking your plumbing. Remove your pump and check the impeller. I have gone periods of 6 months with all pumps working fine, and had to clean impellers almost daily at other times. What gets caugt in impellers? Anything and everything, two days ago for me it was a loose piece of carbon that managed to get out of the filter.

 

[melev]

Before you do this, pull off the intake strainer and see if you get better flow.

 

[j0tca]

That's good advice. If it's a submersible pump, I would use a bucket and a short length of tube to run test the pump before re-installing it. Just dump it in a 5G bucket and check the flow to see what kind of flow it produces without anyway plumbing.