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Amarinus Lacustris


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Amarinus lacustris are a fully freshwater crab native to almost all parts of Australia, New Zealand, Tasmania and several other islands

Amarinus lacustris are a fully freshwater crab native to almost all parts of Australia, New Zealand, Tasmania and several other islands,

As a breeding guide, I must introduce, that they DO NOT have a larval stage at any point of their life cycle, once females are berried they take between 3-5 weeks until the baby crabs hatch and are released, they are fully formed miniature adult crabs (about 1mm)

For water parameters they are reasonable hardy and accept a wide ranges of conditions ( they have to be expendable as they are an estuarine species, where the pH and salinity changes extremely quickly), mine are kept at a pH of 7-7.5, with water changes done weekly of 25%, the tank has sponge filters (I use sponge filters as they are completely shrimp and crab safe, compared to internal motorised sponge filters and hang on the back filters which are known to suck up baby shrimplets and crablets), they easily breed in the same environment that they are kept in (no need for a specific breeder tank), from what I have witness like shrimp they can only breed when a female sheds her shell, there should be an extremely high ratio of females to males as males will continually harass female crabs (that have just shedded) other wise the males can kill females, however males and females get on perfectly fine when females have not shed recently,

mine are kept in a cold water aquarium which has a large amount of native fissidens, driftwood, sand substrate and porous rocks, baby crabs should be fine if kept in the colony environment however as they need to compete with food with adult crabs you may only get 50% survival rate to adulthood, I overcome this issue by housing females (that are berried) in my 5 segmented tank this mean when the female releases the babies I simply take the female out and put back into the main crab tank, the babies are then grown on until the are about .5cm and added to the main colony tank, I keep mine in a species only aquarium, I have some with cherries and the crabs are quite timid of the shrimp even the HUGE 2cm males XD,

I feed all the same food I do my shrimp, this includes shrimp sinking pellets, algae wafers, carrot and other safe vegetables,

I did have Amarinus Laevis however I did find the quite regularly predated on my shrimp :shrk:(this is subjective, as I know people have had no trouble with them and shrimp), also I stopped keeping them because of their complicated life cycle,

all in all, easy to care for, easy to feed, just keep with non aggressive fish (they can be acclimatised to tropical), fully formed babies, extremely shrimp safe.

*images may appear different depending on your computer settings, also if you want to use my images please contact me before copying them/using them

(The crabs range from a light sandy colour, blonde, brown, and dark brown - depending on environment/day and night

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