That's a lovely looking tank you have there.
However I have to question the addition of the carp and tench? Both are strictly cold water species, and really too large a species for an indoor tank. Common carp can grow to in excess of 40lb (18Kg) in the wild in the UK, and similarly tench can easily grow to over 8lb (3.5Kg) - both fish are also naturally patrolling species that are designed to forage over large areas of a lake. They are also both voracious bottom feeders - the carp in particular can cause massive clouds of mud and silt whilst feeding in the wild, and will likely uproot your plants in due course.
Also bear in mind that carp are omnivorous (they have very powerful pharyngeal teeth in their throats - strong enough to crack mussel shells) and happily munch on fish fry and small amphibians in the wild, and crustacea and snails are a common food source, so they'll more than likely have a go at your smaller tetra when they have chance, and will most certainly eat your shrimp and snails if you have any.