Very odd neon tetra behaviour

[Fungi]

Our neons have been extremely easy fish to keep thus far, of an original school of ten only one has died and they have always kept to themselves.
Yesterday we did a huge gravel-vac and water change (50%) in order to change the aquascape. We added a rock feature and an air stone so that the air bubbles under it. We cleaned and scrubbed the rocks heavily as they haven't been in a tank for about two years, we got them second-hand with another tank.

The rocks are towards the back of the tank, and we moved the light to the front (after one half of the glass cover was accidently smashed). There's a teracotta *pot and a driftwood log that have been there since the beginning. Also my brother added a small tacky skull ornament, which I made sure he had washed and scrubbed before he added. The tank is sparsely planted as many of the plants have died, but there is a balance between hidey-holes and free swimming space that the rams greatly appreciate.

We temporarily placed Glad-wrap as a seal so's none of the fish would jump out. The lighting is now much more subdued. The tetras are going crazy, they're flitting around the tank rapidly and rubbing themselves on eachother, some are trying to nip the others' faces, and some are running up and down the glass on the side.

They've still retained all of their colours, if not, they're more bright than I've ever seen them.
They have no manifest physical symptoms of ilness, it's just behavioural.

Tank size is 50L
Tankmates are:
6 rams (5 blue, one gold)
1 small angel
1 betta
9 neon tetras (the ones I'm talking 'bout)
3 bristlenose plecos (small, about 2.5")
(We've been told that we're overstocked before, we haven't added any new fishes to the tank)

I'll get water params up as soon as they've been checked.

Thought I should give as much information as possible

Is this a problem of the massive tank re-modelling? Are they 'in the mood'? Is it the newly added rocks leaking something into the tank? Or is this all symptomatic of a greater problem with the tank?

Thanks in advance for your help,
Will

 

[oscar_con]

neons don't like alot of light, so they're just probably more active because they feel more secure.

 

[mellowvision]

is it possible that whatever you used to clean, bleach or whatever, got into the tank?

 

[Aphotic Phoenix]

There's a teracotta potplant

Sorry...that gave me a chuckle.

 

[Fungi]

Haha, sorry, you know what I meant...
I used no bleach when cleaning the new additions to the tank, just tap-water and lots of scrubbing

 

[dmzAquarius]

Often when I do a siginificant water change, my fish seem especially active and "peppy." I chalk it up to feeling good because of the new water...?

 

[Firebelly__girl]

You have all these fish in a 50 liter tank? isnt that somewhere around 13 gallons?

 

[Visualeyes2]

they are schooling fish and schooling fish do that sometimes. also, most fish will be more energetic after the "dust has settled" after a water change. i don't know why but they just are.

 

[Fungi]

You have all these fish in a 50 liter tank? isnt that somewhere around 13 gallons?

Yes, it is

If it's them all happy about the tank changed, then I'm happy
It's good because they're not looking ill, just hyper

 

[Hooked Newbie]

Few thoughts... My fish tend to "party" at water changes. You are definitely overstocked (And, I've been there) and need to give into MTS or return some fish. Maybe at least in the near term, remove some of the decor to increase the actual water volume? Water params would be good too.