Just knocked this one up.. probably missed alsorts out of it but it gives you an idea. Any specific questions feel free to PM me.
False Water Cobra/Brazilian Smooth Snake (Hydrodynastes gigas)
The FWC, more properly known as the Brazilian Smooth Snake, is native to a large proportion of South America including Columbia, Bolivia, areas of Argentina, Paraguay and Brazil. The snake typically has a background colour of mid-brown with darker banding and irregular patternation, occasionally with additional paler markings circling the darker spots. Ventrally they are usually pale or golden in colour with occasional dark flecking. Typically these snakes attain a length of 6-7ft. These snakes are capable of “hooding” by flattening their necks and upper bodies when alarmed, gaining them their name False water “cobra”.
Young FWC “hooding up”
These snakes are often labelled as aggressive and unpredictable, though this needn’t be the case with captive bred or well handled animals; indeed all the captive bred FWCs I have owned became very tame with regular handling. WC or under-handled adults are not recommended for those with little experience of aggressive snakes as an aggressive FWC is often fast and relentless – such snakes are not shy to bite if upset. These animals can tame down over time, though it cannot be guaranteed.
Housing
Hatchlings can be kept in any secure, lidded, ventilated tub, such as commercially available faunariums or contico tubs which are easily upgraded as your snake matures. The FWCs fast metabolism and endless appetite mean an easy to clean setup is a must and for this reason I recommend using a basic setup with paper substrate for youngsters.
FWCs are hardy captives and simply require a variety of hides (across the warm and cool ends of the viv or tub) and a large waterbowl, as they spend a good proportion of the day soaking. Hatchlings also seem to appreciate some plant cover (use plastic where possible) for security. Sample setups are shown below (please note a larger waterbowl would be desirable in picture 1).

Adults should be housed in a vivarium of 4’x18”x18” minimum – these large, active snakes should not be confined to small tubs. Please note that FWCs are commonly viv territorial and it may be necessary to remove them using a snake hook for handling.
Heating, Humidity and Lighting
A day time high of 82-85F appears to be ideal for this species, ideally with a cool end around 10F lower (75F). Temperatures much above 85F seem to provoke heat stress in this species and should be avoided. Heating may be provided by heat mats, cable or ceramic heating elements (I do not recommend bulbs as they cannot be used for night-time heating; there is evidence to suggest snakes can see even red light).
Humidity should be maintained at 50-80%, this can be done by regularly misting, using a humidity retaining substrate and adding a large waterbowl.
There is no evidence to suggest FWCs require UV lighting, though a regular day/night cycle should be provided.
Feeding
False water cobras are well known for being voracious feeders and their strong feeding response makes using feeding tongs a must! Be aware that they often strike blindly and wildly when food is on offer! Freeze/thawed rodents are the best food source and are taken readily.
Their high metabolic rate means FWCs benefit from being fed more regularly than many colubrids; personally I feed mine twice per week on relatively small food items. These snakes are real herp room dustbins and will literally eat all you can offer if you let them.
A note on venom
In recent years the venom of the FWC has been compared to that of the Timber rattlesnake, however this is primarily based on LD50 levels. It should be noted that LD50 levels do not take into account venom yield or venom delivery system effectiveness. In reality the FWCs low venom yield and poor dentition require it to “chew” for some time to release a significant amount of venom into the puncture. Typical symptoms include oedema, pruritis and excessive or prolonged bleeding. In rare cases an allergic reaction resulting in anaphylaxis may occur.