gph questions

[cgray]

The flow of the tank is everything together or is it just the powerhead GPH? Learning everything from books and two of them go against each other. One says to add the total gph of everything - filters and powerheads. Another says just the flow of the powerheads is totaled into the tanks GPH. I need to know which one it is.

Also, looking into reverse flow powerheads and the two that I found are Hagens and Penguins. Now the Hagens are rated at one GPH at normal flow but in reverse flow that GPH is reduced by more than 50%. The Penguin does not list it's reverse-flow GPH, should I just take off the same percent if I was to buy a Penguin?

Thanx,
cgray

 

[czcz]

Depends on what you need GPH for. If "flow" means water movement, everything matters. If you're calculating rate of filtration/water turnover, only your filter(s) GPH matters. Easy to add a DIY filter to a PH and make these numbers the same.

I have a Penguin 660, and it has no reverse flow. Unless it says otherwise, I assume a PH is one-way.

HTH

** http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=4628&N=2004+22788
Reverse flow kit is apparently an elbow that fits over the outlet, per Marineland's site.

 

[TankGirl]

There is flow and there is flow. If you are talking about filtration and not powerhead water movement, then you need to pay close attention to gph and purchase one size up from the gph rated for your tank. Powerheads and water movement basically just eliminate "dead" spots in your tank and are not (to me at least) a major factor in filtration concerns.

 

[cgray]

wouldn't that elbow change the GPH output. And on those you would have to use the "sponge" filter. At least that's what it looks like to me in the reverse kit for Penguin. Both together should alter the hell out of the GPH. With the Hagen, how do they work, motor cranks the other direction?

If your using an UGF with the powerheads, would this count for filtering?

 

[czcz]

wouldn't that elbow change the GPH output.

According to sellers claim in link above, no. Perhaps it doesn't affect pressure/rate because water is going down (no head height issues)?

And on those you would have to use the "sponge" filter. At least that's what it looks like to me in the reverse kit for Penguin. Both together should alter the hell out of the GPH.

I don't see why you can't use any 90deg elbow provided it fits/seals. IMO an elbow doesn't make 660 reverse flow, just redirected output, but I'm relatively new Sponge or rubbermaid+filter floss DIY (plans at thekrib) on PH would affect flow, but with maintenence of media its not that restrictive (I use a plastic scrubber). Link above implies rate was measued with sponge and elbow. If exact GPH matters, you should experiment and time how long it takes to fill container of known volume.

With the Hagen, how do they work, motor cranks the other direction?

FWIW as I've been told by LFS, yes. I do not own one.

If your using an UGF with the powerheads, would this count for filtering?

Sure. Consider UGF plate, elbows, gravel would also impede flow.

HTH

 

[cgray]

Another problem is if I was to use these reverse flows how do I get any current movement for my fish? Isn't this one of the main functions of a PH? I know they're suppose to help in the UGF's biological cycle but also they create currents for the fish....right?

 

[czcz]

Then dont use UGF and use prefilters and pH forward flow instead. If you want to use UGF GPH still gets moved. What is it you're trying to do? If you want current to go in a certain direction you can manipulate the intake and outtakes of your PH. Here is great site re river tank if you want ideas: http://loaches.com/river_tank.html . And Here is a pic of my adapted HOB intake to control flow (outflow is on the other side of tank) using same principle as that article.