Too late to edit a previous post and there's at least a few incorrect specs in there (I got specs from others/manufacturers/fasttech and there's way too much exageration or misinformation on height and ml capacity, but written below are upgraded specs confirmed by syringe or caliper in youtube videos).
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If you just want specs, just skip to the specs post lol, the rest of this is kinda just rant and reasoning.
All I'm wanting is decent mls in a compact, short single-coil RTA WITH JUICE FLOW CONTROL (JF). They exist, but not with JF.
I know a lot of people are Okay without JF but I've had plenty of tanks leak and I'm sure you have too. Even if you wick perfectly, tanks just leak sometimes. I don't know why. It'll be working fine and then leak a few days later or something.
When you refill, it leaks.
When it's hot outside or in a hot car etc, it leaks no matter how perfect you wick.
If you want to change juice to something with more % flavor (flavor base is thinner than VG) or use a different VG/PG/Flavor ratio, it leaks.
Leave tank on its side, it leaks.
But, close the JF a bit and there's nothing to worry about. I mean, JF is only a metal-to-metal connection which juice can definitely still seep through, but it usually doesn't.
Funny thing is I vape thick %100 VG, often flavorless, and I still get leaks. I stuff plenty of cotton through the coil it's a miracle it doesn't rip when inserted. I tried rolled compacted cotton to fit even more but it still leaks. I try looser cotton, it still leaks. I build ~5 wrap 3mm dual fused kanthal claptons BTW. I cut the cotton so it ends up barely touching the bottom of the deck, sometimes I'll stuff more in the wicking channel, sometimes I'll cut some of the tail long-ways to reduce it - it still leaks.
I think leaking is what recently fried the charging circuit on my DNA200 mod. Worked perfectly for over a year until I had very bad leaking with defective premade coils. USB still works fine in escribe.
I just don't see why they would omit JF on tanks. All it requires is the coil chamber overlap the wicking ports and then a small ~3mm knurled ring to adjust JF. There's no reason NOT to add JF unless to save like 3mm on height, you can just leave the JF open if you want. Every popular vape reviewer suggests to close the JF at least when filling a tank to prevent leaking, so even if they somehow never get leaks like I described, I know they obviously get leaks when refilling without JF.
So I'm personally currently avoiding all tanks without JF at the expense of not being able to choose some that are shorter and hold good mls such as the Kylin mini 24.3mm x 43mm w/ tip and holds 5ml which are good specs but no JF.
Most people will say they're ok without JF but maybe I have bad luck, but even if not, there are still times when tanks leak regardless (hot in summer or hot in car etc). I'm not going to debate JF vs non JF. I'm not even going to assume that I'm building wrong because I've built like 100 times with various methods but it usually ends up leaking at least a little bit. My o-rings look fine also BTW. If you are okay with no JF, hopefully the size and ml specs I list will help you find an RTA that doesn't have JF.
At least now I know exactly what to look for when searching for a new tank next time- I just want decent mls in a short tank with JF. I don't have to nit pick 2mm on height or .5ml capacity which takes a long time if there's a lot of RTAs to search through because they're not all listed in one place either. I know the general dimensions and capacity that are 'good enough' for a compact single coil rta with JF I'm waiting for.
All these youtube vape reviewers and bloggers, half of the video is building a coil and then vaping on it trying to convince you to buy it via a link in description or something so they get a cut of the sale or trying to make things seem better than they are so that manufacturers are more likely to send them more free stuff for review -- there needs to be a person who lists tanks and MODs in chronological order as they come out so you can get out of the loop for a few months or whatever and then check that list and only need to sort through what you missed if you've already refined all of the previous attys (and mods and RDAs etc). With syringe and caliper confirmed specs for each item, I would pay for something like that.
For my bigger dual coil tank for use with dual/triple 3000mAh 18650s, I did find a few that hold good mls and have JF such as the Ammit dual coil
25mmx55mm w/ tip caliper confirmed tall mode (5.75ml syringe confirmed, not 6ml), 27mm at tank is quote bulky though. But I haven't found anything that has JF and holds much juice for a single coil compact RTA for use with a small, single 18650 MOD.
The only tank I'm getting that doesn't have JF is the Berserker MTL only because it's an MTL and none of the other MTLs have JF that I know of except the kayfun if it is an MTL. I'm hoping MTL will recreate the performance I liked from the original Protank 1 in flavor etc (minus the leaking/gurgling of the protank 1-2 of course). If the berserker gives me hell with leaking etc, a kayfun does have JF and is a tight-draw MTL if I'm not mistaken but they're quite tall for a single 18650 small MOD (24mm VT75 nano) and/or might not hold decent mls for a single coil fused clapton build for thick vapor if they have a short version.
Notes:
--Some tanks are meant for dual coil but they're postless decks such as the Ammit dual coil, and yes you sort of can put a single coil in there, I've seen it in videos you just stagger to the other side's screw, but this is at the expense of a few things which I'm not sure will give such a good vape. Some tanks have a silicone insert you can plug the other side to make a single coil but personally I'm concerned about a silicone plug being so close to the coil possibly leaching and/or melting.
With a single coil in a deck meant for dual, you'll need extra cotton in the wick holes because they're meant to fit two wicks in each side. Maybe closing the JF (if it has) will work though just using a regular amount of single coil wick.
Some of these decks have a raised air flow metal area in the center that the coil isn't supposed to be above when in dual coil mode, so you'd have to raise the single coil up above that raised area a bit (only about 2-3mm) but still may mean it takes a bit longer to wick if you chain vape. I think the main concern though is that a single in a deck meant for dual will be too air'y of a draw, thus resulting in sub par performance.
This is why I omitted trying to 'hack' a single build into a dual coil RTA in hopes that the specs of said dual coil RTA would be good for my small, single 18650 single coil RTA (single coil to conserve battery life). I asked about building dual thin wound wire builds to make these dual deck RTAs save battery on a smaller single 18650 MOD but the consensus was that a single clapton would be better.
--clickable air flow is really a step backwards IMO. I have a tfv8, and when the air flow ring gets juiced from a leak or just heated from vaping, it spins easily but I've never had a problem with it moving by itself. Reviewers/vapers seem to be always concered about air flow stopping at fully open instead of just spinning around but I don't see that need either. I'm not sure about the other RTAs, but the Ammit dual coil which I'm getting does have clicking air flow. This means you probably can't precisely tune it, it might not be able to be set in between clicks. I never though I'd care about air flow being so precise but I recently changed types of coils in my sub ohm tank and found that I want to have the air flow just right with the new coils, and this fine adjustment may not be possible if the air adjustment CLICKS to the next amount. Whistling air flow is something else though, and yes that does suck and should be a thing of the past by now if there's a way to avoid that (honey comb inlet or something IDK).
-Kylin mini is 24.3mm x 43mm w/ tip and holds 5ml which are good specs but has no JF. I don't know what manufactuers are even thinking making tanks that aren't on that same par of capacity and compact size (and with JF, but even if not, still, why even make it larger and hold less if it's obviously possible with the Kylin mini to have those specs)? I guess larger build deck and/or chimney are plusses at the expense of reduced juice capacity and larger dimensions but if I'm not mistaken these tanks are machine-made and all they have to do is change the specs in the computer and the machines makes it however size they want - they don't have to make a whole seperate assembly line of machinery to change a tanks's specs slightly such as to make a V1 with larger juice capacity and a V2 with smaller capacity but with a larger deck and chimney.
We use big coils now that are like 5X the amount of vapor as a "1.8 ohm single coil round wire build", we need tanks to hold more mls. I know the 2ml TPD law is used in some countries but many tanks have a 3ml mode or only max out at like 4ml and still are quite larger than the Kylin 5ml. But all they even have to add for most of these tanks is an optional bubble glass and the capacity is increased by about 2ml. This 3ml and 3.5 ml capacity is just stupid - that's pratically all we had with a friggin 18mm protank 1 using tiny 1.8ohm round coils.
- The Jual KS RTA is a great concept. It keeps the overall MOD height low and holds 7 frigin mls. They should make that in glass instead of plastic and it's still a compact overall MOD but can maybe hold 10mls.
-Top Air Flow (TAF) RTAs
I said previously that TAF is good to prevent leaking, but in reality it won't prevent FLOODING the build deck like JF does. If you have flooding for any reason (heat, add thinner juice, etc), a TAF RTA will flood the tank and possibly render it useless. No I have NOT used a TAF RTA but in theory what happens is the deck will just fill with juice instead of leaking out air flow on bottom-air tanks. With the Zeus RTA TAF, it has sort of straws on each side that go to the TAF intake. If you blow out to clear a flood, it might clean out the chamber and make it vape-able again (similar to how you can blow out on a bottom air flow RTA and jucie will get on youd MOD but you might be able to continue vaping fine, at least for a while). However I don't see this as a replacement for JF because with JF you can at least correct the problem and continue vaping whereas with TAF it might just keep flooding until you're all out of juice.
And also I'm not sure about this if it's even noticable or not but I would think bottom air flow is better performance than TAF anyway.
Thus I voided out all RTAs with top air flow as a replacement for JF. The Wotofo Sapor is TAF and has JF too but doesn't have the height or ml specs I was looking for in a single coil RTA smaller version (sapor is dual-only velocity deck, and doesn't hold as much as other dual coil JF RTAs if considering as a dual coil RTA). With other TAF RTAs besides the Zeus which has those sort of straws chambers, the others like the Engine RTA and Sapor have the In and Out air flow at the top under the mouthpiece, so if you get a flood and blow out, it might not even clear the flood and thus not be vape'able until emptied and rebuilt. With JF, you can close it off a bit and vape fine until you rebuild or just keep it like that.
-I do a lot of physical work and stuff, so I want a small single 18650 3000 mAh MOD to not interfere in pocket, but not something miniature like a juul which barely holds any liquid or battery. The larger Ammit dual coil RTA I'm getting is 25x55mm w/ tip caliper confirmed 5.75ml syringe confirmed. 27mm tank - which is good capacity and not super tall but would likely be too bulky for my mini set up VT75 nano (not to mention kill single 18650 quick with dual claptons). Bigger tanks like this I'll use at other times with a dual 18650 VT250s 6000 mAh.
I'm just mentioning the reason why I nit picked the specs so much to find a small single coil RTA that holds decent mls. A few mms in tank height isn't really anything, maybe the size of a chick pea or something, and it may be possible to find smaller drip tips than the stock ones, but I still want the smaller set-up to be small as possible because once you start accepting taller and bulkier tanks in order to hold more juice, before you know it you're considering the largest tanks available. I could just use an RDA on the smaller MOD and a 5-10ml bottle of juice in pocket, and I love RDAs except for the whole dripping process of course, but when I'm in the middle of doing something and want to hit the vape real quick, i don't want to be bothered by opening bottles and dripping etc. Also, to me, squonks and RDTAs are basically just genesis atomizers, top coil sub-par wicking vs bottom coil RTAs. They're just Genesis style tanks that have small wells and they wick upward and take longer to wick and I prefer to drip onto the top of the coils instead of just juicing the bottom of the wicks like a squonk does. But I will consider a few RDTAs or RDAs with very deep wells because they're very compact and don't leak if you can close off the air, and then just keep a 5-10ml bottle in pocket keeps the overall set-up compact and light.
But, I'd rather just wait and hope a compact bottom coil RTA comes out that holds decent mls with JF.
I actually still have to check through all (well, most) Sub Ohm Tanks (premade coil tanks) for a small MOD sub tank, and something big to replace my TFV8 which has giant premade coils and an RBA deck insert but hopefully with JF which the TFV8 doesn't have, and I don't like the silicone gasket on the TFV8 fill port because it possibly leaches unknown chemicals and it also expands from juice and eventually you can't even close the tank but I figured out that cutting off some of it lets it to close again and won't leak unless you leave it sideways.
I'm not trying to go too crazy with nit picking specs on the sub tanks even though I actually usually prefer to just use a premade $2 sub tank coil (only about $1 a week for coils) vs building an RTA, but this whole process is just a PITA. Once I get a list of tanks to then find the TRUE capacity and dimension of from videos with calipers and syringes, it's not too bad, but just making the list to begin with is pain because there's so much to choose from and I don't even know where to start (Like I said, if someone, a reviewer or vape aficionado or someone would make a chronological list of gear as it's released, and maybe also list caliper and syringe true specs of as much of it as they can, or at least just the manufacturer's specs (often exagerated though) I would pay/donate for that because it makes keeping up with vape gear so much easier.