Poorly kept axolotls in zoo

I recently visited an aquarium (I won't say which one, just in case), and found that they kept axoltols there. To Me, they looked to be kept in very poor conditions, but I'm quite new to axolotl keeping, so I just wanted to check here before i send them an email (they're all very nice there, and I'm certain they're not doing it deliberately, so I'm sure if I just send a very polite email, they'll make some changes to treat them better).
The problems that I could see were:
. All the gills were very small for their size (some were only stumps and the axis where 30cm long!), most were deformed (twisted with odd branching parts), and had almist no "frilly bits" (Sorry, im not sure what the technical term is!)
. The tank (which I very roughly measured to be about 6×my 30 gallom tank) was home to 20 axolitls. I keep 2 in a 30 gallon tank (and at the moment they're only tiny babies, and I know I'll probably have to get a bigger tank when they grow- these were huge!). So, at a stretch that should only have had 12 axis in it (2×6). Although, this is only a rough estimate, so this might not be a problem
. The tails of most of them had been bitten so often they had healed with large dents in (possibly another sign they didn't have enough space, if they were attacking each other that much) and one was so bitten he hardly had any of of top of his tail left!
. Many of them had fungus of their face and body- at this point, It wasn't much on most, but surely it will spread unless something's done about It?
. Finally, the water was not kept at all still. Every ten minutes (ish) a "water wave" would be pushed into the tank (if youve been to aquariums, youll know what I mean- it's hard to explain!) That physically pushes all of the axis back, and leaves the water rocking untill the next wave.
It's almost impossible to tell if theyre stressed by any of this, because their gills are almost non existent (im really not sure how they manage to get enough oxygen to breath, but it certainly means they hardly move!). Could someone assure me please that I'm not overreacting, And informing the aquarium (again, politly and helpfully) would be the best course of action. Thank you!
Ps it won't let me put on attachments!! It just gets stuck uploading them for hours, whether I have internet or not!

They look in good condition as does their tank. You should have spoken to somebody at the aquarium, would have saved you writing an essay. The wave is part of the filtration system, water quality is more important than water volume, judging care on stocking density isn't accurate. Gills don't indicate stress so the fact that you can't see them pointing forward is irrelevant, small gills can he a sign of well oxygenated water and not just poor water quality. The white spots I can see in the pics are not fungus but pigment/lack of pigment/vitalagio , these are often seen on older animals. You don't see a lot of pics of older axolotls in axolotl groups as most of them get wasted by lack of care well before they can develop a few spots.
Any complaints about the gravel ?

Thank you for the info- I didn't speak to anyone there, because I didn't want to make a fuss before I'd checked that anything was wrong- which, thanks to your reply, I've found was probably the right thing to do. Just a couple of questioms though. Firstly, I know the water wave is part of the filtration, but surely that is stressing them out? We know for a fact moving water upsets axolotls, And that's not just moving, that's tidal wave! And also, I thought curled forward gills did indicate stress? I'm glad its not fungus though! And actually, I forgot to mention the gravel- that was another point- it's much smaller than their head, and easily swallowable. (Oh and ps please don't take this personally, I'm really not criticising the aquarium in any way, it's just i know how many animals they have to look after (they run a seal resuce as well) so I just thought if something was wrong, And the axis were being overlooked, I could nicely point it out. If nothing's wrong, then great! But I don't want to see them suffering if something is).

Just speak to them about your concerns, I have not see the "tidal wave" so can't comment on it's suitability for an axolotl tank but Axolotls come from still/slow moving waterways so are not designed for this kind of water movement and the commonly held view is that it stresses them out. The gravel is a bit big, I wouldn't use it.