Selecting the Proper Pump, An Introduction

[Dkarc@Aol.com]

Over the past several months, it has come to my attention that a lot of hobbyists dont really know how to select a water pump for their application. Well today, im hoping to atleast partially demystify this subject for many. Below is a link to article I wrote not too long ago on how to properly size and choose a water pump. It's not ment to be 100% complete in it's content or theory, but rather a basic guide.

Here is the link to the PDF file of the article....if anyone else knows of an easier way to get it transfered directly to the forum, let me know please! (having trouble with the charts not transferring over properly).

http://www.mediafire.com/?sharekey=ec0719fe895016fb67cd7f7bd65f7eef91e624eb 10b028df947708e37b913e74

-Ryan

[Dkarc@Aol.com]

I also wanted to let everyone know that this article is the first of a series I intend to write on basic fishroom/hatchery equipment sizing and usage...basically reference guides for people to learn and make educated decisions based upon their needs.

-Ryan

[babakaty]

hey Ryan,

Great write-up. I was just trying to figure this stuff out the other day. Can't wait for the next piece. And BTW, I love the Aquatic Eco Systems catalog I got at the NADA show. It's in its 3rd week of #1 on the bedtime reading list :)

[Lukan]

Well Done. Wish i had this information way back then when i was learning about plumbing for my reeftank. Well written. I look forward to your next article.

[dean9922]

Great post...this should be a sticky.....I'm currently looking at pumps for some applications I will be doing in my fish room and this helps a ton...thanks

[Dkarc@Aol.com]

Thanks for the positive feedback everyone. Really appreciate it. Hopefully I can get the aeration article up in a few weeks...

-Ryan

[RockRiverfish]

Nicely done.

Simple enough for the novice to digest without getting bogged down in too much physics.

Looking forward to future articles.

[Dkarc@Aol.com]

Nicely done.

Simple enough for the novice to digest without getting bogged down in too much physics.

Looking forward to future articles.

That was my goal.

My next article will be on aeration, but that is an enormous topic that I will either have to omit certain topics entirely or do it in several installments. Even then, some parts could be a little involved, but i'll do my best.

-Ryan

[pete321]

Hi Ryan
Great article!
How would you select a pump for a central system that was on 4 levels?

[Dkarc@Aol.com]

Hi Ryan
Great article!
How would you select a pump for a central system that was on 4 levels?

Great question! It definitely takes some time to sit down, write/draw it all out, and do some math to make sure you figure everything out.

First thing I do is take each level, one level at a time, and figure out the flow requirements. Determine how many times per hour you want those tanks to turnover. Figure out how many gallons per minute that flow rate is (ex: 500gal of water, 3x turnover, 1,500GPH = 25GPM).Then go to the next level and do the same....and so on, and so on. Once you have all the flow requirements for each level, add them up. Once you have this grand total flow rate, you can start looking at your TDH.

Start with the obvious one, your vertical head. Find the highest point in the system and use that number. Based upon your overall flow rate, look at your basic friction loss referenced to the proper sized pipe for that flow for the main distribution manifold. Here is where a lot of people screw up and grossly oversize their pumps....when figuring out your friction loss for the system, separate out each level and calculate the friction loss going to that level, NOT the total flow moving in the system. Calculate for the 25GPM moving through that level, not the 100GPM moving through all 4 levels. Calculate ONLY the friction loss through the piping, do not calculate for vertical head loss from the pump to that level.

Once you have all the friction losses for all levels, add them up. Given for proper sized piping, and not an extreme pipe length (100+ft), those numbers should be relatively small. Add into that your vertical head to get your overall TDH. From there it follows exactly like in my article when matching a pump for the flow and TDH.


-Ryan

[pete321]

Great. Thanks!

[tcyiu]

Bravo. Very nicely done.

Tim

[Dkarc@Aol.com]

Bravo. Very nicely done.

Tim

Thank you. I have been very busy with work these past few months and havent had proper time to sit down to finish my other articles im doing. Hopefully i'll get them done sometime soon...

-Ryan

[aalbina]

Thanks Ryan - this is terrific. Based on the information in your article, I was able to calculate my TDH from my storage tank in the basement to my tanks on the first floor (TDH=18ft) with one 90 and one 45 degree turn. I was able to find a submersible clear water pump on clearance locally that exceeded the TDH by 10 ft for $35.00. Stopped by the hardware store and got all the CPVC fittings and pipe and an RV drinking water safe 25ft hose. Installed a ball valve garden hose faucet recessed into an oversize electrical box at the top of the first basement stair. Connected everything over the weekend and filled my tanks without humping water up the stairs in buckets this weekend. Thanks for the great information! Got everything I needed to do this project from start to finish for about $80.00 - and thanks to your article I got it right the first time.

Just a quick question - if I reduce the flow a bit at the ball valve - is that going to damage the pump at all?

Thanks again.

Adam

[Dkarc@Aol.com]

Thanks Ryan - this is terrific. Based on the information in your article, I was able to calculate my TDH from my storage tank in the basement to my tanks on the first floor (TDH=18ft) with one 90 and one 45 degree turn. I was able to find a submersible clear water pump on clearance locally that exceeded the TDH by 10 ft for $35.00. Stopped by the hardware store and got all the CPVC fittings and pipe and an RV drinking water safe 25ft hose. Installed a ball valve garden hose faucet recessed into an oversize electrical box at the top of the first basement stair. Connected everything over the weekend and filled my tanks without humping water up the stairs in buckets this weekend. Thanks for the great information! Got everything I needed to do this project from start to finish for about $80.00 - and thanks to your article I got it right the first time.

Just a quick question - if I reduce the flow a bit at the ball valve - is that going to damage the pump at all?

Thanks again.

Adam

It really depends on the kind of pump you have. In general, 30% closed is about as far as you want to go (safely). Any further and you risk damage to the pump. But of course, it also depends on the type of pump you have.

-Ryan

[ericatdallas]

Thanks for the tutorial!

[jeralar]

Great info on this thread! I need I'll the help I can get with plumbing issues. Always having to call San Jose plumbers in my area for sump pump issues in my basement, but now that I'm getting into aquariums it's more of an issue. Learning a lot from these types of threads though, thanks!