Which external water pump for my DIY co2 reactor build?

[Pinkmummy79]

I have all I need for my (foxfish) co2 reactor but before I plough on and build it inot my filter return pipe I am now considering using a stand alone water pump just for the reactor and build a full length 4 foot spray bar.
My tank is a 4 foot Fluval Vicenza 260 bow front, currently running 2 x JBL e1501 cannisters, presurised co2 and ei ferts with a newwave circulation pump in tank at present to assist with cireculation. The tank is relatively deep too being 64cm.
My concern is obviously flow and circulation. I don't wish to compromise the filter output by adding a restriction such as the reactor so if I can add in a tool just for the job then i'll save for what is best.
Now my research has so far led me to Eheim universal water pumps, being quiet (is this so??) and reliable, but my decision is which one?
I would hazzard a guess at my current total ltr/ph with both e1501's full of media is approx 2000, maybe even less??
discounting my powerhead as I may be able to do away with this once the water pump is fitted, there are 2 options, Eheim 1250 universal pump with 1200 ltr/hr or the larger 1260 pump giving 2280 ltr/hr.

I'm unsure if the 1250 will be strong enough to run the reactor and utilise the four foot spray bar? and would the 1260 be too much?
this is new to me so any experience in these matters would be welcomed, oh and any different options would also be considered thanks

 

[Palm Tree]

I like Grundfos pumps, they are normally used for central heating. They generally are the best pumps to go for as they are extremely reliable and last years, as well as being 3 speed pumps so you can adjust flow by restricting power consumption unlike normal pumps where you would just restrict the outlet flow.
You would need to get an aqua turn conversion kit so that they will not rust due to the oxygenated water - Aqua-Turn 3 speed Grundfos Pump conversion for DIY Koi Ponds and water features | eBay
You can pick up used pumps off ebay cheaply, however not the lowest wattage and a costly option in the long run.
If I were you I’d just stick it on one of the Jbl's, they are 1400lph each (but that's the pump rating so it will be less than that) and just buy another circulation pump or E1501.

 

[Pinkmummy79]

hmmmm, my original plan was to make two of foxfish's design of reactor running one each off the JBL 1501 's, which I may still do, only funds are allowing me to do one at a time, due to my tank being deep and bow fronted, I'm trying to keep Clive's advice about improving flow and circulation at the forefront of my plans at all times, so spraybars running from the rear and if necessary i'll keep the circ pump in there and as you suggest maybe add another if required, all depends on how much flow maybe lost due to the inclusion of the reactors, unfortunately there is only so much room under the tank for stuff, so a 3rd e1501 to run reactors is out unfortunately, it's getting tight in there now with 2 big filters and FE etc, long term running costs are also important, I may look into the Grundfos thanks for the heads up Palm Tree.

 

[Palm Tree]

You would have better flow overall using only one reactor, but then co2 will be going through one spray bar only. Two reactors would be good, one on each JBL and two circulation pumps (rated about 1500-2500lph each). If you had 2x 2ft spray bars at the back top of the tank pointing towards the front wall and very slightly downwards and the circulation pumps on the back wall as well, you could easily be achieving 4500-7000 lph so 20x turnover bare minimum. The reason I praise the circulation pumps is because they are ultra-low wattage, the 2700lph newave is 2.8w, a 2500lph grundfos 15/50 is 65w at zero head pressure. If your paying 15p a unit, the 2.8w pump running 24/7 365 days a year will cost you £3.68, the 65w Grundfos will cost you £85.41 a year (the eheim 1260 is also 65w so it will cost the same), and that is eye watering £££ just to add a bit extra flow to compensate for a CO2 reactor.
PS- You would be better off with 3 lower output circulation pumps, say newave 1.6 (1600lph) than 2 bigger ones as it will give you a more even flow distribution.

 

[Pinkmummy79]

The circ pump I am using is the smallest Newave 1.6 it's adjustable with a sleeve, however I usually have it fully open,Prior to buying this I did have the 2.7 but found it way too much, stems were bent double and fish were hiding in corners, so I sold it and have the funds stashed in the kitchen cupboard towards anything else the tank needs, I would buy another of these at the drop of a hat they're great!
I think i'm sorted then, 2 reactors one off each filter and another newave 1.6, ooh and a couple of good needle valves for when I need to split my co2 from the JBL reg.
Cool, I like to have a solid plan, i'll look forward to putting things in place, excited now, daft I know but this hobby has grabbed me by the danglies over the last 6 months and gives me a bit of me time away from work and the kids
Cheers Palm Tree, you've helped me have some confidence in what I was planning.