Backyard Aquaponics
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Sounds like your needs are significantly different to the revisited question, where cost was a significant issue.
If desiring LiPo batteries, then cheap is not your want..
..
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I run a system with renewable energy as a separate set of circuits in the house. You've got to be careful to not cross connect things like stereo in one and DVD in the other. Other than that this type of system is super cheap to setup. Whereas gridtie is outrageous and unless you buy anti-islanding yours goes down when the grid goes down. let me see if I can find my page on my setup... there's a lengthy discussion here about wiring batteries with the Otherpower forum members

I had to mod two bolts to fit the connections where four lugs connect, after I realised there was going to be five cables, plus the #10 diversion load controller leads, I made one more interconnect for those and tied them into the main connector

FYI I picked up these old telcom UPS batteries for $400 locally. There're huge, they weigh like 100 pounds per. Telephone companies swap them every four years or so.

I don't want LiFePhosphate batteries I want reliable power for my system. It just seems that the LiFePhosphate batteries are the best choice. 1 because you can discharge them much more than a lead acid and 2 because you can discharge them and charge them much faster than a Lead acid.

When specking the batteries one of the head aches I was coming up against was not just the size of the battery bank in Amphrs or kWhrs but how efficiently it could be charged and discharged. A layman would think that if I have 20kWhr battery bank I can run a 5kW system for four hours. Thing is with lead acids the more you discharge them the less durable they are so if you keep the depth of discharge to less then 25% then that means I've only got 5kWhr to play with. No problem that means I just have to have the generator kick in every hour to recharge the batteries when the solar panels are not producing. Problem is that you can't discharge the batteries that quickly because without some pretty serious losses. Lead acids don't take or give up a charge very efficiently if you ask a lot of them in a hurry they can even over heat. So in order to avoid that issue I need an even bigger battery bank not for the capacity but so that the level of discharge and re charge can be slower relative to the size of the battery.

LiFePhosphates can be discharged further which mean more usable charge from less batteries and can be discharged more quickly which means I can have a smaller battery bank again as long as I'm happy with the generator coming on more frequently. Plus I can get a larger generator so that it is not on for as long but the battery bank can handle the faster rate of charge of a larger generator.

Couple of years and it will be these Stuart http://insideevs.com/toshiba-called-sup ... system-uk/

Or very possibly these.
http://www.vanadiumbattery.com/
http://www.redtenergy.com/energystorageproducts

from what I just read the LiFePhosphates look like a very good battery

They are, I'm getting better than 99% charge to discharge operating efficiency from mine, which I installed in 2012.

I'm looking to set up a solar powered pump in a pond... I don't want a battery, just for the pump to work when the sun shines.

I'm not at all savvy about electronics, and I've tried researching, it seems that a panel, a mppt controller and a 12v pump would be the components I need?

I only want to move around 300-400 lph.

Can anyone tell me if I'm on the right track? How I should size match the components etc

Cheers

For that sort of quantity your best bet is to buy a kit which includes the pump and panels.

As Stuart says above... plenty of these small solar pumps available at various online stores.

cheers guys. It's just that most of the solar pump kits I've seen come with a battery. I was hoping to avoid having a battery just because I don't require the water to be moving through the night, it takes up room, and as I understand they are economically and environmentally costly.

I will have another look for battery-less kits. Any recommendations in terms of brands and models?

Just out of interest, at what would be the threshold where its becomes logical to go the route of separate components? 200w panel say?

Hard to know what is available in the UK from here, but most hardware and irrigation stores there should have at least 1 model of solar only pump available.

Here you go.

Range of solar pump kits apparently only one has a battery.,

https://creativepumps.com.au/product/re ... anel-kits/