Leaves curled/clawed - need help identifying problem

A few months ago my partner and I decided we would start a small garden on our balcony. He bought a bunch of different herb seeds and some chilli seeds. We started with Anaheim and planned to move on to bigger and better things if we were successful. We live in Queensland, Australia, so it seemed like we'd have hot enough temperatures for chillies!
 
We had three chilli seeds sprout - two of them took off, while the other one was unable to shed the seed properly (the leaves were caught in it). Fast forward many weeks, and the two large chilli plants started flowering. We lost our first few chillies to a lack of calcium (BER), gave the plants a good dose of Rooster Booster and they popped up heaps more flowers and have been setting more fruit.
 
The problem:
A few weeks back we potted the third, stunted chilli into a larger pot, as it looked like something was wrong with the leaves (they'd started curling down) and it needed more room to grow. Now our other two chilli plants have some leaves doing it as well. I thought at first it was a nutrient deficiency (as we'd had that happen to us already) but after doing lots of searching it seems it might be pest related. I've seen similar images with mention of aphids, thrips and broad mites.
 
The leaves' veins have thickened and bent on some leaves so much that the leaf curls down on itself and stretches the leaf tissue, that tears if disturbed too much. On the leaves that are curling down, the underside of the leaf is very shiny, and some of the bent leaves are shiny on top near the stem. We've found small white/clear bugs on the underside of leaves, normally wedged in the nooks between veins, that move very, very quickly when disturbed. So far I haven't found too many - there's generally only one or two of them on a leaf, and only on a few of the leaves I check. They're less than a mm big and hard to focus on with my camera - I can try and get a video of some if it'll help.
 
Some of the leaves on the larger chilli plants are doing something different - they're shrivelling at the tip of the leaf. I have no idea what's doing this and it seems we have multiple problems/things attacking our two larger plants.
 
We ordered neem oil and have sprayed a solution onto the leaves (top and underside) but I found a few of those white bugs still around a day after spraying, and the leaves have gotten worse since then. I'm not sure how often I should be spraying the leaves (once a week, once a month?). Any help with this problem would be greatly appreciated - I love my plants and don't want to lose them
 
 
The stunted chilli plant:
 

 
 
 
 
 
 
The two larger chilli plants:
 

 

 

Overwatering and aphids to my mind but I'll leave it to the experts to jump in.  Are they drying out or close to dry before you water them?  Aphids or scale on the last photo - hard to tell with the picture- pyrethrum works for me, others use neem oil but check on frequency as apparently it build up.  

I don't think I'm overwatering - I read that it's okay to wait until the chilli's leaves are just starting to go limp and then give them a drink, which for the two large chilli plants is every 3-4 days and the smaller one is about once a week. The mix is about 2/3 potting mix (it was quite chunky, had bark bits and stuff in it) and 1/3 perlite. There's a thin layer of coarse sand on top of the plants with Rooster Booster pellets, as it tends to get a bit stinky when I water.
 
I read a few accounts of scale not really moving - the things we have move really fast when disturbed. So far we've only used the neem solution once, as I'm worried about overdoing it! I'll look into pyrethrum, thanks

OK, scratch that. You answered some of my questions as I was typing.
 
I see no indications of any pest at this point, so administering pest control in the form of neem and pyrethrin is not advised. Never treat without confirming the ailment.
What has changed prior to the plants exhibiting these symptoms? What are the values of the rooster booster pellets? do you know the pH of any of your components and the contents on your growing media?
How hot is it in Queensland during the day and how much direct sunlight are your plants exposed to?

To be honest I don't know what changed, as I'm sure the stunted chilli's leaves had started curling before we repotted (same makeup 2 parts potting mix, 1 part perlite). It was done using a new bag of potting mix, which came with fungus gnats but they seemed to clear off once the mix was in the pots and had a chance to dry out.
 
Rooster Booster is 3:2:2:7 with trace elements (N:K:Ca, in the form of gypsum), which we selected because it's mild strength and natural (chook manure pellets). I gave about 2/3 strength recommended dose weeks ago when our first few chillies got BER. Since then our two large plants started shooting new leaves and a lot of new flowers, four of which are now very large fruits. PDF here
 
Temps last month were generally 21-31 degrees C, with a few days at 35. It's starting to cool down this month. The plants get a few hours of sun in the morning before the sun goes overhead (and is blocked by the roof).
 
I don't know what the pH of the soil is. I'll get a hold of test strips and get that done ASAP. I should also mention that we'd been watering with tap water since first planting everything, but when our avocado plant started browning at the tips two weeks ago and I read about the potential salt content in tap water, we switched to using water that's been through our ceramic water filter for it. Maybe I should do that for the chillies too.
 
So much to learn 

I want to say probably over-fertilization.

Definitely check the PH. I recently had a similar problem, I thought I could get away from my premixed 50 gallon reservoirs and hand watering by just using City Water from the tap. It worked well last year when I switched about mid season. This year I started off with City Tap Water once I potted up. It took about two weeks but all my plants crashed and looked like yours. They just shriveled up with no yellowing or apparent pest infestation. I checked PH and it was at 9.5! I treated the water to 6.5 and watered everything really good. So far it looks like they're on their way to a full recovery. Good luck. 

What you call "crinkled" tips looks a lot like the beginnings of fertilizer burn, but I also agree with SL3 that you should check the pH. The crinkling, when not caught early enough, can often be found over the major surface of a leaf, but not always. Additionally, the light brown spots may occur with over-fertilizing. The leaves curling under more like a fold, however, is often a symptom of something else. So the plants may have more than one thing going on. Here's a link to some grow guides you might find helpful. I'd suggest backing off on the fertilizer as a first step. Regarding the fast-moving bugs, I agree that you should start addressing them now. You might try to find beneficial insects or go with Neem. Sorry - racking my brain but what those fast-moving bugs are isn't coming to me ATM.

Thanks for all the responses guys. I guess the good thing about the Rooster Booster is that they're pellets and they're just sitting at the top of the soil, so they're easy to remove and flush the pot. I do think they've helped with the calcium deficiency (only added one lot of pellets and haven't seen another fruit with BER, and the plants have put on tons of new growth) but it does say they're slow release and last months, so maybe the plants have had enough now? I can remove them tomorrow when it isn't so dark outside, it's after midnight here!
 
I tried to get a video of these little critters hiding under the leaves - I apologise for the poor quality, it's a phone camera and the things are so tiny. This one was under one of the hooked leaves, and you can see near the end of the video there's a tear in the leaf from me trying to flatten it out to show off the bug.
 
Chilli Bug

The bug does not appear to be a pest or at least I cannot positively ID it as such. With that in mind, I would not treat for pest as you really do not know it is one. could be a small light colored spider looking for pests.
The first pic, leaf on the right looks like sun scald which is why I asked about direct sun. this generally happens when moving plants into the sun without a proper hardening off period.
 
Water with salt or improper pH could definitely be a culprit. If you can get distilled or RO water, I would do so ASAP. That would eliminate bad water from the equation. If you know any other growers or have a grow shop that can test for TDS and would oblige you, get that done as well. It is always nice to know how much salt you may be fighting with.
 
Lose the rooster boosters for a while. Until you know whether or not your soil is actually deficient, you dont want to be adding anything in excess as that could be problematic in itself.

ChilliK said:

 
 
So much to learn          

Click to expand...

 
     FIFY

ChilliK said:

To be honest I don't know what changed, as I'm sure the stunted chilli's leaves had started curling before we repotted (same makeup 2 parts potting mix, 1 part perlite). It was done using a new bag of potting mix, which came with fungus gnats but they seemed to clear off once the mix was in the pots and had a chance to dry out.
 
Rooster Booster is 3:2:2:7 with trace elements (N:K:Ca, in the form of gypsum), which we selected because it's mild strength and natural (chook manure pellets). I gave about 2/3 strength recommended dose weeks ago when our first few chillies got BER. Since then our two large plants started shooting new leaves and a lot of new flowers, four of which are now very large fruits. PDF here
 
Temps last month were generally 21-31 degrees C, with a few days at 35. It's starting to cool down this month. The plants get a few hours of sun in the morning before the sun goes overhead (and is blocked by the roof).
 
I don't know what the pH of the soil is. I'll get a hold of test strips and get that done ASAP. I should also mention that we'd been watering with tap water since first planting everything, but when our avocado plant started browning at the tips two weeks ago and I read about the potential salt content in tap water, we switched to using water that's been through our ceramic water filter for it. Maybe I should do that for the chillies too.
 
So much to learn 

Click to expand...

if you can , always microwave your soil before potting , kills eggs , larvae critters ! learned that from a  ol' veteran grower friend . i have a micro. out in the garage just for such . 

Haha, Hybrid, thanks. It is exciting, but all quite daunting as well. This has turned from a "let's start a little balcony garden" to these plants being like pets.
 
Moruga, I had read about baking the soil but neither of us were willing to use the oven we cook food in! Would adding boiling water to soil have a similar effect?
 
Capcom, it could actually be sun scald - the stunted chilli used to sit at the back of the table but when we put more plants on it, it got shuffled to the front (closer to the balcony edge). It probably gets an extra few hours of direct light there. It's been moved now 
 
The pellets have been taken off and the soil given a flush with water from the filter.
 
About the little white/yellow/clear creatures - they're multiplying, quite quickly since I stopped squashing them on sight after starting this thread (as they might be beneficials?). I can find at least one on every young leaf, and they seem to like hanging out on the chilli fruits too. Quite a few on each of the big fruits. They seem to move around a lot and then will wander up under under where the fruit joins the plant.
I also found this leaf where there were four that I could see, and there seems to be some kind of collection of dust, like a nest. These little things are freaking me out a bit, I won't lie. 
There's also some fine strands between some of the uppermost leaves. Not sure if we have a resident spider, couldn't see one. 
 

 
 

seems like mites

Good ones or bad ones? If they're good ones, they have to be eating something to be multiplying so fast, and it would be good to know what they're after. If they're bad ones, they're eating our plants and can dia 

i would just assume theyre bad and nuke them, i never met a mite i liked

Obviously bad. Theybarent doing anything g beneficial, right?

Yeah....looks like it could be spider mites. Misting your plants in the evening will help i believe until your sure of what course your gonna take, as im pretty sure they like dry conditions. 

able eye said:

i would just assume theyre bad and nuke them, i never met a mite i liked

Click to expand...

but you still could, or you mite.

So it's been a fortnight since I last posted - lots has been happening and unfortunately I haven't had time to post. I took pictures when I remembered though so hopefully will be able to bring things up to speed.
 
The two big chilli plants are doing about the same - I'm just on monitoring mode with those little white bugs, as they very well could be hunting little nasties (see below). We had a week of cold weather with the temps dropping below 15 degrees C at night, so I was bringing them inside at night to try to keep them warm, as they have a lot of chillies growing still!
 
Little Stunty is... I'm not really sure how it is. After spraying it with the Neem solution and giving it a small dose of Rooster Booster over a month ago, it had started trying to grow new leaves (around the time I first posted this thread - you can see them in the fist picture, on the left). Around two weeks ago the new leaves were looking all shrivelled and warped. When I shone a torch on them, I noticed that quite a few of the specks of "dust" on the leaves were moving. Freaky, freaky stuff. These things are maybe a 5th of the size of the white bugs that are on the larger chilli plants. Sprayed it with Neem again.
Went out again today, couldn't see anything moving at the top but there were more specks moving on the newest leaves halfway down the stem that look almost normal. Is it okay to spray with Neem once every week or two if I wash it off the next day?
 
It seems like Little Stunty, being a weaker plant, has attracted the specks and that either the bigger plants are stronger and not showing it as much (will give them a thorough look over tomorrow), or those white bugs I found are actually hunting these moving specks. There have been some positives (one of the four larger chillies finally turned red!) but I guess I should start a grow thread to show that off?
 
Left is a shot from about two weeks ago, right is a shot from today. Poor little Stunty