Changing the input side will do more to increase flow than changing out the
output side, making water available to the pump. A restricted input will
cause the pump to cavitate and wear prematurely. If you are happy with the
current flow, then you do not have to increase the discharge pipe size, but
by changing it you would at least double the flow.

--
RichToyBox
http://www.geocities.com/richtoybox/index.html
"gng" wrote in message
...
Thanks - so the big question is whether it would make any difference at
all
if I changed out the input feed tubing with 2" but left the output (to
filter, uv, and waterfall) 1.5". Right now the waterfall is looking
great -
should I just forget about it?

"RichToyBox" wrote in message
news:gsARc.227496$%_6.203565@attbi_s01...
Based on the flow rating of the Sequence 7200, the friction loss for 1.5
inch pipe would be about 50 foot of head per hundred foot of pipe, which
means the pump is not capable of getting that flow. For 2 inch pipe the
head loss is about 11 feet, and that is reasonable. For the 1.5 inch
pipe,
the flow is probably about 1/2 what it is capable of.

--
RichToyBox
http://www.geocities.com/richtoybox/index.html
"gng" wrote in message
...
Thanks - it actually looks pretty good right now since the filter was
cleaned. But it looks as if I should change out the 1.5" to 2" if I
want
a
bigger waterfall. From what I can see, it looks pretty significant.
Anyone
out there change out pipe size and notice a big difference? There are
some
areas where it must stay 1.5", such as the pipe that is cemented into
the
waterfall. Will this negate me changing out the rest of the pipe? Is
the
flow only as good as the smallest pipe size?

"chagoi" wrote in message
...
chagoi wrote:


larger pipe = less restriction = more flow

I know this is for PVC, but it shows the relationship between
different
sizes



Table1: Saturation Flow Rates for Schedule 40 PVC
Pipe Size Approximate Saturation Flow Rate
1 inch 25 GPM 1500 GPH
1 ½ inch 60 GPM 3600 GPH
2 inch 150 GPM 9000 GPH


Table 2: Maximum Recommended Flow Rates And Pump Sizes
for Various Pipe Sizes
Pipe Size Max Pump Size Approx. Flow Rate with Max Pump
Size
1 inch 1/3 hp 15 GPM 900 GPH
1 ¼ inch ½ hp 25 GPM 2100 GPH
1 ½ inch ½ hp 45 GPM 2700 GPH
2 inch 1 hp 75 GPM 4500 GPH
2 ½ inch 1 ½ hp 110 GPM 6600 GPH
3 inch 2 hp 200 GPM 12000 GPH




-- Bigger is better, and less is more
/\/\ike
Chagoi
http://ourkoipond.com


try this for tables 1 & 2
http://ourkoipond.com/psafr.htm

--
/\/\ike
Chagoi
http://ourkoipond.com