Thanks for the links! I'm only trying to move enough liquid for 3gal batches so I think I might try to source two pumps with a little more power. Topsflo type TS5 15pv is rated for 3gal per minute
http://www.amazon.com/gp/product/B0075J6S3W/?tag=skimlinks_replacement-20
and get the following bits for power
http://www.amazon.com/dp/B013QLXTVQ/?tag=skimlinks_replacement-20
and connecting
http://www.amazon.com/dp/B005CMP434/?tag=skimlinks_replacement-20
I think I can have two pumps ready to run for only a little more than the price of 1 march/chugger
The tan pumps come in a few different configurations, the basic 24v 3gallon per minute version which I currently use and then there are more powerful versions all the way up to 5 gallons per minute.
The basic 12v version works fine but they do not pump as much as the basic 24v version
They are all food grade and were designed for this use. actually they were designed for drinking fountian use from what I have found but they are made of food grade PPS plastic and have fully coated sealed magnets that do not touch the liquid. Unlike the topsflo pump you linked which have 3 things going against it that I'm aware of.
1) the magnet is not coated and is exposed to the wort.
2 )since it was designed as a solar hot water pump it has MPPT technology built into it which is basically voltage buck/boost tech to take lower or higher curent or voltage and step it up to a higher or lower fixed amount to run the pump depending on varying power coming in from the solar panels powering it.
3) it has thermal protection built in which may cause it to shut down when attempting to pump boiling temp liquid..
Technically the type of plastic on the black topsflo is only rated to be foodsafe to 170degrees from what I've read but many state these are foodgrade even though the manufacturer themselves said in an email they are technically not because of the exposed magnet. Topsflo is a distributor of pumps from many other manufactures I dont think they actually manufacture or design any of them however they do give specs to meet when placing their orders like most modern companies that dont do their own manufacturing.
I had one of those pumps and learned this the hard way.
That said If you really want to buy a topsflo branded pump you can buy the generic tan pumps rebranded by them and sold for over twice the normal price for piece of mind
I wouldnt bother myself...
I have 7 of the tan ones now 4 24v and 3 12v... I only use the 24v ones with a cheap pwm speed controller. I have 3 of them hardplumbed into my setup below... been using them for years with no issues. I bought them all from different sellers and they are all the same except they come in two color variants and different voltage/size motors. The parts are all 100% interchangable.
I will repeat the advice that you need a real powersupply not the underpowered and often mislabeled wall worts that are rated at power during a lightning strike...
You want at least 1 amp rms for each pump. I control all mine off one power supply mounted in my panel.
The number one reason these pumps get a bad rap is people try to pump grain through them and they are too small for that.
#2 reason is people do not use the correct power supply or the supply is starting to fail and they mistakenly blame the pump. #3 would be people drop them and break them... they are plastic and $20 not stainless and $150... use accordingly and they work awesome!