Inline or Submersible Pumps

[PrettyFishies]

I bought a 2nd hand wet/dry to gut and use as a sump... but the owner sealed the bulkhead to use a submersible pump for return. Now I am at a crossroads...it's acrylic, so drilling should be easy...the quetsion is is there any difference performance wise or maintenance wise for inline vs submersible?

And if submersible... is a Mag9.5 strong enough for a 90gal?

 

[fishfreek]

And if submersible... is a Mag9.5 strong enough for a 90gal?

What is the head height? If thats your only circulation pump it would be on the low end of what I would consiter to be acceptable. But then again I like ALOT of flow.

Pumps push less water the higher the head height is from the pump to the top of your tank. So if a pump does lets say 900GPH at 0' head it might only do 700GPH at 4' head.

The specs on the mag 9.5 can be found below as far as head height loss.

http://www.drsfostersmith.com/product/add_info.cfm?pCatId=9372

The main differences between submersible and external is the following.

Submersible pumps are the easiet to install since you dont have to worry about a bulk head or extra plumbing from the sump to the pump. On the down side they are water cooled so they will transfer some heat into the water. How much this heat affects the tank is up for debate.

External pumps can usually be found to be more powerful or atleast have the potental to be more powerful than submersible pumps. These pumps are often air cooled so they do not transfer heat to the water like their submersible cousins. External pumps often require a few drops of light gun oil to be placed on the berings every X months. My little giant suggests it every 6-8 months. You have to deal with getting a bulkhead fitting and also plumbing from the sump to the pump. Its a wise idea to also install some ball valves so you can remove the pump for service/replacmetn with out having to drain the sump.

 

[loganj]

I would drill the sump either way. The Mag pumps will run external just fine and it will make a lot neater installation. While it will still transfer some heat to the water, it will be less than if it was in the sump. Should you decide to go with an external pump, Champion Lighting has a pretty good selection. I like the Little Giants.
Logan J

 

[Barney]

I really like my little giant external pump. Easy to maintain, oiled every 3 months, just 2 drops of 3 in 1 lubrication oil. This way I can maintain my temperature. Noise is just a hum that can be fixed with a sound absorber, like placing a piece of cardboard underneath.

I also have another tank which I use a submersible pump, my heater rarely is used but there in case. I don't meant to sound like they run hot, but I have replaced 3 so far versus the same external pump Iv'e had on the other tank.

 

[cal91666]

I'm running a Mag 12 on a 90gal externally and have had no problem.