Tiny moths attacking my orange tree.

Anyone seen these? I will try and grab a photo, but they are very tiny, about 1mm or less in size, the leaves are covered in them and everything is sticky with honey dew.

Anyone know what they are?

Whitefly?

Personally I'm trying to steer away from spraying chemicals these days, but for a bad whitefly infestation I don't really know of any alternative. I'd spray with an insecticide, maybe a pyrethrum, and likely it will take 2 or 3 sprays over 1-2 weeks to get rid of them. Try to target the affected citrus only, and spray early morning or evening when the wind is down and the bees are not there.

Maybe someone else has a better alternative to commercial insecticides.

Whitefly and a more friendly alternative would be a spraying oil, tho pyrethrum is not such a bad thing and can be used with oils for a much more effective control.

Yup, that looks like them, do they cause problems?
Ive just bought this property earlier this year and we have a citrus tree, i expect they have been always around.

Like a number of pests, in large numbers they are a problem, in small numbers they are not - but they never stay in small numbers for long.

I have found that IF you keep a close eye on your plants & trees you can spot the beginnings of these problems before they turn into a full blown infestation. If you spot things like whitefly and aphids early enough you can avoid full infestation simply by squishing them on a few leaves or removing a few leaves. Whitefly and aphids are usually spotted on the undersides of leaves. You have to get down low and look up to see them.

Whitefly (and aphids) can be a problem and should be removed if seen. Their feeding on leaves, buds and stems will cause growth to turn yellow and become stunted. Aphids seem to like young new growth but whitefly seem to be happy under larger older leaves. A big enough infestation can seriously harm plants. Some whitefly are also vectors for viral diseases.

Steel blue ladybugs and lacewings feed on whitefly. If you had these whitefly predators in your citrus and the infestation was minimal you could leave it and maybe give things a hand by squishing the whitefly (rub your thumb along the leaf).

It sounds like your infestation is already well established, so probably time to spray - targeted at the infested tree/bush.

And spray every 5 days to break the life cycle. Use Pyrethrum spray.

Pyrethrum will kill all insects, so if you have blossoms on the tree being visited by bees, or if you already have ladybirds hanging around, try a mineral oil spray or soap spray first until the blossoms are gone. Dilute soap spray to wash off the bugs.
Read the instructions on the mineral oil pack for dilutions - it'll be more dilute than what's usually used for winter spraying.