Help with Return pump.

**rockstarnsc83** · 03-22-2010, 09:50 AM

Well, Ive read it multiple times on different sites. Is it true is what I was asking..or would I be fine with the 300 gph overflow. I already had the overflow ,so it was just one thing I didnt have to buy..but if 600gph is much better, I can get one. I hadnt bought a return pump or anything yet..so I could still research more pumps at 4 foot of head to go with the 600 gph overflow.

I need to know something asap, because there is a great deal on ebay going for a used cpr 600pgh overflow. and I would need to get it within 3 days. Also I can plan the pump accordingly either way.

**rockstarnsc83** · 03-22-2010, 01:56 PM

I thought I would have gotten more feedback here but I did some more reading and they are not talking about turnover rate on just the overflow, but just in general, with the powerheads and such. So I will be just fine using my 300gph overflow and my ecotech marine vortech powerhead.

**saxman** · 03-23-2010, 02:51 PM

one thing to consider is that your chiller will add roughly 6 feet of head to your setup, so make sure you account for that (i'm running six chillers ATM, so i've plumbed my share of them). personally, i think a 500 gph pump will be a bit small by the time you add the rest of the head loss to the equation. i always go a bit more than i think i need in terms of GPH. in your case, i'd be looking at 700 gph minimum.

here's a quick sketch showing the "bleed-off valve" back to your sump to tune any excess flow from the pump should it be "too much":

also, if you're running a CPR-style O/F, be sure to get the optional aqualifter pump. the CPR-style O/F's are notorious for breaking siphon upon power outages and pump stoppage for routine tank work.

**rockstarnsc83** · 03-23-2010, 04:10 PM

chiller adds about 6 foot of pressure? really? 100 percent sure on that? if that was the case..it would be 6 foot plus 4 foot.. 10 foot of head pressure of course...thats a bit much. Thanks for the little sketch and yes I have the aqualifter pump for the overflow.

**rockstarnsc83** · 03-23-2010, 05:02 PM

and if that is the case..then as of right now I already have around 10 foot of head pressure right now.. my 29 gallon biocube has a fluval fx5 hooked to it..which is hooked to the chiller and then outputed to the tank.....I even had a 10 gallon tank that had the 300gph overflow on it draining back into the biocube. it all worked out well and the fluval fx5 is rated for up to 607 gph. so I think a 700 to 750 gph pump will be just fine.

**saxman** · 03-23-2010, 07:04 PM

it's kind of a "rule of thumb" for chillers...obviously, some are "worse" than others, but most mfrs don't come right out and tell you how much head a chiller adds to your setup, altho if you can get a dialog going with them, they will sometimes tell you if you ask.

i played with this a bit, as my last setup is plumbed so i can remove the chiller from the system easily (ya gotta love true-union valves!). there was significant difference in the flow without the chiller (in fact, i had to dial the flow back a fair amount via the bleed-off valve). i actually tried two different chillers in the loop, and oddly enuff, the 1/5 hp was worse than the 1/3 hp (3/4" vs 1" in/out).

the moral to the story, at least the one i go by, is "when in doubt, up-size the pump a bit", as you can always bleed some flow back if needed. you can't add something that isn't there, but you can subtract what IS there.

i should also mention that another reason i do this is because i HATE PH's...they're ugly, they're a PITA, etc. i like to design my flow in from the start via the mains and/or CL's, but i'm kind of a fanatic that way (just ask Renee/seahorsedreams). all i want in my tanks are the things i want to see.

HTH

**rockstarnsc83** · 03-23-2010, 08:51 PM

I got a vortech mp40 w to install. =)

**rockstarnsc83** · 03-24-2010, 06:29 PM

I will most likely go with the mag drive 7. 480 gph at 4 feet.... 400gph at 6 feet... 300 gph at 8 feet.

**rockstarnsc83** · 03-25-2010, 11:07 PM

I went with the RIO PLUS 2500. about 49 watts. 782 gph at 0 head. 529 gph at 4 feet and 375gph at 6 feet.

V · 03-26-2010, 09:58 AM

Im pretty much along the same wavelength there sax in regards to fitments of movement & thats it. Its all in the design.

Although, besides the logical aspect of additional equipment, why do people feel its required to run chillers inline. Just have it on a closed independent loop near the RT pickup

**AZDesertRat** · 03-26-2010, 10:16 AM

But that requires an additional pump which means more power consumption and added heat gain for the chiller to overcome. I am trying to reduce the number of pumps I use in my systems by combining functions such as feeding the calcium reactor and media reactor with the same pump or even feed the skimmer from the overflow to reduce power erquirements and added heat. So far I have been successful enough to eliminate my chiller and go back to fans only year round in Phoenix with the tank at 79-81 year round.

V · 03-26-2010, 10:37 AM

Thats good going.
Dont get me wrong, i see the logic behind it. however if your pump choice is factored on all of the above, your less likely to run into a stone wall. All im saying is its pointless buying something thats vastly over rated driving costs up anyways, when you can run a single or groupings with very little fuss & complexity