Automatic feeders and fountains, priced

Divide each feeder's price by its hopper and you get the same answer, near enough. The PetLibro Granary is £70 and holds 3 litres of dry food, up to 6 meals a day. The PetSafe Simply Feed is £132 and holds 5.6 litres (24 cups), up to 12 meals a day. That's about £23.50 per litre of hopper either way, at the prices read on 2 November 2026. So capacity costs the same. The difference lies in what comes with each one.

I haven't run any of these. This comes from Pets at Home's listings, Catit's filter page and zooplus.co.uk. The order above is by what each listing says you must buy beyond the box to keep it running, fewest things first. Price plays no part in it.

Feeders: read the power line

PetLibro Granary. The set includes a power adapter, a bowl and holder and a desiccant bag. USB-C runs it. Three D batteries are for backup if the power fails, and they aren't included, so one small purchase stands between you and a feeder that survives a power cut. Pets at Home lists up to 50 portions and a 10-second voice recording. Kibble has to be 2 to 15 mm and dry.

PetSafe Simply Feed. Nothing runs until you've bought 4 D-cell batteries or adaptor, both sold separately. In exchange it handles dry and semi-moist food up to 2 cm across, portions from 30 ml to 948 ml, and a slow-feed mode that spreads a meal over 15 minutes. The listing says it's best for cats and small to medium dogs. Parts and the steel bowl can go in the dishwasher. The conveyor is hand wash only.

Neither page lists wet food. A cat on pouches needs a different plan.

Buyer scores aren't a fair contest yet. PetSafe has 4.1 out of 5 from 88 reviews, and the Granary has 5 from a single review. I'd trust the first and ignore the second.

How long a hopper lasts

Neither page gives this, and litres don't convert to grams without knowing your kibble. The bill's formula gets you halfway. A 4.5 kg neutered cat at 70 x 4.5^0.75 x 1.2 needs about 260 kcal a day. At the bill's assumed 3,500 kcal/kg, that's about 74 g of dry food. Weigh a level litre of your own food, multiply by the hopper size, then divide by that daily figure. Check your bag for the real calories, because 3,500 is only our assumption.

The formula is only a starting point for one animal, so watch your cat's weight, and take any concern to your vet. A feeder also can't tell you a cat has stopped eating. Someone still needs to look.

Fountains: count the filters

Same tank, different habits. The PIXI holds 2.5 litres, the Dockstream 2.5 litres, and both pumps stop when the water runs out, by Pets at Home's account.

zooplus.co.uk listed 6 PIXI filters at £10.09 on 2 November 2026, or £20.18 a year on Catit's schedule. I didn't find a price for the Dockstream's filters, so I can't total that side. Up front it's £79 for the Dockstream against £36 for the PIXI, read the same day. That's a lot to pay for not needing a socket, though with no socket near the right spot it's the one of these two that works.

The Dockstream's page quotes 23 dB. The PIXI's gives no noise figure. Treat that 23 as a seller's number, with no test named. The Dockstream's page also says "always supervise your pet while using the fountain", which fits oddly with a machine bought for when you aren't there.

For a closer look at one of these, read the Catit Pixi review. The rest of the list is on the feeders and fountains page, and if you're pricing other running costs, here's what cat litter costs by type.