Pumps

[jslaney]

Thanks for the advice everyone,

I was hoping to mount the pump as an external pump which I believe both the quite one and mag drives are capable of.

Tony, you mentioned that you should not have more then 7 time flow through your sump for fears of producing micro bubles. I am assuming you mean the sump volume. Unfortunatly my Sump is only 20 gal and thats all I can really fit under there. That means I will only be able to push roughly 140 gal/hr to the main 72 Gal tank. Thats only a 2 time turnover. Is this correct. I guess I can make up the rest of the flow with power heads but I was hoping to avoid that.

In addition, I would love to check out your tanks and ask you a million questions. Unfortunatly I rarely head to the south. I will give you shout next time I do though.

Just when I thought I was coming to a decision I now have to check out reviews for sedras and enhiems.

On another note. Why dont many people use quite ones. I am assuming they are fairly quite as their name suggests and they put out more flow per dollar then most of the more expensive pumps out there?

Thanks again,

Jon

[Delphinus]

It's just a name They didn't used to be all that quiet, the new models may not be too bad but it is just a brand name. I don't have any experience with them, so I don't know how they compare to others. The old models also used to have reliability issues. They were external pumps made of ceramic and they were prone to heat stress cracking the units. The current models are not like that, however, totally different design. They are probably fine pumps.

Anyhow, no - you don't want 2 times turnover. Sorry, I meant whole system turnover. So basically volume of water in the tank, plus volume of water in the sump, minus whatever for rock and so on. With a 72g tank, 20g sump (running at probably half way full roughly - more on this later), you're probably looking at around 80 gals total volume, you want 5-7 times THIS volume per hour (so 480 gallons per hour). Further, you have to look at the pump curve data and figure out what gph it pushes around 4-6 feet of head pressure. So you're probably wanting a pump that's rated for 700gph at 0' head which is going to translate to (hopefully) around 500gph realistically for a sump return.

You can go higher of course, but two things to take into account: the higher the flow, the higher the water level in the tank above the overflow line. And the higher the flow, the faster the water travels in the sump. If air bubbles from the overflow make it to the pump intake, then you'll have persistent microbubbles. So that's why I prefer to not oversize the sump return pump.

But you do want a minimum flowrate so that if you keep a heater in the sump, the heat from that heater is making it to the main tank.

Hope this is making sense, sorry if it's overwhelming.

PS. Forgot the "more about this later" part. Make sure that whatever volume of water in the main tank that is above the overflow and any kind of anti-siphon break in the return plumbing can fit into the sump in the event of a power fail or pump shutoff. If you run the 20g sump at 1/2 way full then you have room for 10g (which is probably plenty). I'm sure you know this but just thought I'd be safe and mention it nonetheless.

[jslaney]

That seems much more reasonable. Ya, overfilling you sump seems like a common rookie error which I am sure I will do no matter how much I try to avoid it. I think as long as I fill the tank while the pump is off I should be ok.
I will definitly look more into the sedras.

Thanks again,

Jon

[Delphinus]

One more thought (sorry to keep dumping ideas on you ), if you run a pump externally, use flex PVC or at least vinyl hose for the connections to the pump. If you go rigid PVC all the way, the pump vibrations transfer into the plumbing (and sump) and you get a hummmmmmmm kind of effect. Also a mouse pad works well for under the pump to further dampen any pump vibration.

Flex PVC is the best, works/glues exactly the same as rigid PVC, same fittings, etc. you can pick it up from Western Pump in town. You can also get unions there (although some Rona's do carry unions now - nice ).

[andresont]

External pumps are always more noise.
If you want it to be quiet Eheim is the most reliable and quiet, to make a quiet oferflow look up durso pipe

JM2CW

[jslaney]

I had read about the flex PVC somewhere but did not know it was readily avialable. I was thinking of using it due to my poor handyman skills but sound dampening makes it a slam dunk. I was trying to think of what I could put under the pump as well. The mouse pad idea is great.

I was going to go with an external pump due to heat transfer as my condo gets warm in the summer. I deffinitly do not plan on getting a chiller but I really want this quiet. Are internal Pumps really that much quieter?

That Durso link has a much better picture then the one I posted earlier.

Thanks,

Jon

[andresont]

Originally Posted by jslaney

Are internal Pumps really that much quieter?

That Durso link has a much better picture then the one I posted earlier.

Thanks,

Jon

Eheim is silent compare to Mag drives and mag drives are quieter then externals.
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