Off the wall plumbing question

[vasubandu]

I am setting up an algal turf scrubber above my aquarium. The water input will be either from a small powerhead in my overflow or a larger pump in my sump below. I don't need much flow, but would rather regulate too much than to have too little.

I will essentially pump the water up 20 inches, then a right turn for 6 inches, then a right turn up 36 inches from the overflow or 78 inches from the sump, then a right angle and 2 feet horizontally to the scrubber.

My overflow has openings that are 3 by 6 inches, so something like an Eheim 1000 series is the best I could fit in there. That pump would have three feet of real head and a number of right angle turns. If I go the sump method, I would use a mag pump, maybe a Mag 3. In terms of flow and not burning out the pump, which method makes more sense. Assume that routing the water is equally easy with a slight edge to the sump.

Now the more interesting question. All of the pumps I am looking at have a 1/2 inch outlet. The inlets to the scrubber is 3/4 inch. So at some point, I will have to convert from 1/2 inch to 3/4 inch pipe. I could do it vertically as the water is pumped up to the scrubber or horizontally after the water has reached the height. Does it make any difference? Part of me wants to put a 3/4 inch adapter at the pump and make it all 3/4 inch. But part of me wonders if that would be more water weight against the pump and therefore more head.

 

[Saltstick]

imo, stick with the 1/2 till the very end and put an adapter from 1/2 to 3/4 that way you get more head power. but i'm not a genius so just my input.

 

[big t]

I don't have any real input except for your head pressure question. Head pressure would be reduced by using all 3/4" pipe because it will have less frictional water loss. Vertical head pressure is the same whether you use 1/4" pipe or 4" pipe.

 

[Myteemouse]

Heres a link for you It is a head loss calculator..

http://www.reefcentral.com/calc/hlc2.php

 

[gas4544]

Do you have a target waterflow that you want to supply to the scrubber?

It may come down to running some tests with different combinations of pumps and pipes. Do you have any of the candidate pumps on hand? If so, you could run your initial tests with pump(s) that you already have without buying pumps that you may or may not use. Personally, I like to have some extra pumps on hand to enable me to make plumbing changes to my skimmers or to my sump.

If you would like to control the flow to the scrubber, I suggest going with a quiet, reliable pump that provides excess flow. Then plumb a gate valve inline between the pump and the scrubber. That makes it easy to vary the flow throught the scrubber until you find the amount of flow that works best.

When it comes to plumbing, I am big on installing union gate valves. This enables you to fine tune your water flow from completely closed to completely open. Valves make it easier to do maintainance to your pumps, too.

Gary

 

[kgross]

You will get more flow out of the pump if you go to the 3/4 inch as close to the pump as possible (less friction loss).

But other than that, how much flow does your algae scrubber need/want?

 

[vasubandu]

Thanks to all of you for the help. Now I may have the opposite problem. I scored a brand new Eheim 1262 from baseballkid5, so I now have 3/4 inch all the way. But I also have a new question. I need 60-90 gph. The head tool is great, but only goes up the Eheim 1250. It shows 1250 at 5 gph (7 feet of head pressure) with the configuration I have planned (, but the 1250 is 317 gph and less than 7 feet of head, while the 1262 is 900 gph with 11.5 feet of head. If Iuse a Mag 9 instead, it shows 454 gph with 9.5 feet of head pressure.

So here is the question. I assume the 1262 will produce more than I need. If I ratchet the output down with a ball valve to 60-90 gph, will I harm the pump or mkae it run hotter? Thanks again for all your help.

 

[kgross]

That is why many people asked what flow rate you needed.

But you can put a valve on the output of the pump and it will not harm it at all, actually you will use less electricity and less heat if you valve it down.

Kim

 

[gas4544]

Here is a link with some manufacturer's specs and flow charts for Eheim pumps.

http://www.drsfostersmith.com/produ...ubref=AA&ci_src=14110944&ci_sku=0012784000000

Click on the "More Information" tab below the picture of the pump at the top of the page.

I sent you a PM, too.

Gary