As with all grass- or water-types, members of the lotad line need clean water—a lot of it, in fact. An outdoor pond would be ideal, but if this isn’t an option for you, be sure to get a shallow tank that’s wide enough for your lotad to move. Many trainers make the mistake of either getting a tank that’s too small or assuming that a lotad tank is the same as a fish tank, so be sure that you’re buying a tank that’s specifically marketed to surface-dwelling water-types. Either way, lotad will need a lot of space, so they’re not actually ideal urban pokémon unless you have convenient access to a park with a clean pond.
Also note that your lotad will need to spend plenty of time in water and sunlight. Ideally, this means six to eight hours of floating during the day, but it’s possible to separate its sunning times from its soaking times (such as in the case of indoor lotad). If you do this, you will still need to give it at least six hours of each, but if you need to leave your lotad unattended, simply allow it to float in its tank while you’re gone. While lotad generally need plenty of space, many of them won’t move too far from their tanks by themselves, so you can be sure that your lotad will still be there when you get back.
Standard lotad kibble is fine to give your new pokémon, but should you wish to feed yours something other than dry food, lotad are omnivorous and primarily eat berries and insects. Freeze-dried insects are fine, especially because lotad can’t generally tell the difference. Do not feed them anything large or hard (such as larger fruits or pieces of meat) as lotad don’t actually have teeth and rely on what their beaks can mash up to eat.
Upon evolution, lombre is a little less active than lotad and will thus be easier to handle; once you leave your lombre someplace, it will generally stay put without moving. Doubly so if you leave it in direct sunlight. However, ludicolo are extremely difficult to maintain in smaller, urban environments, as evolution increases their energy and stamina and causes them to experience uncontrollable urges to dance, especially around festive music. If you live in an urban environment, it’s highly recommended that you avoid allowing your lombre to come in contact with water stone. Should this happen anyway, clear an area specifically for your ludicolo. A completely empty bedroom should be sufficient. Soundproof this room (for the sake of your neighbors) and usher your ludicolo into it as soon as it looks like it’s about to dance.
Good luck with your new lotad, @slime-beast.
The Pokédex According to Bill 