Grass Shrimp

[tebstan]

I'll post about what I've learned about grass shrimp so far. I'm on a time crunch this morning, so I haven't done a lot of in depth research yet. If anyone else knows anything, please chime in.

These shrimp are often confused because they're tiny and hard to ID without a microscope, but the care of them for feeding purposes shouldn't differ much. The shrimp for sale at Polly's are Palgemonetes vulgaris, commonly called grass shrimp, glass shrimp, marsh grass shrimp, and popcorn shrimp, as well as others I'm sure. (I'm fond of the popcorn shrimp moniker!)

Grass shrimp are eurythermal, they can tolerate a wide range of temperatures. They can also tolerate a wide range of salinity. (As long as properly acclimated, of course.)

They normally eat epiphytic algae, which is a plant that grows on another plant, like spanish moss and mistletoe. I'm hoping this means they'll be good at eating nuisance algae like the slime on glass or hair algae. I'll post when I see results of this being true. They are normally detrivores and algae grazers, but can be cannabilistic and carnivorous in captivity. This seems understandable, if they're kept in a glass box they'll eat what they can to stay alive. So, like with any crab or shrimp, they are "reef safe" with caution. (Although I don't think they stand a chance to be aggressive if there are any hungry fish around!)

They breed as late as October, and can take up to 60 days to hatch, and need a bit of time to grow. They may not be available through the end of winter, as they are collected from the wild, not captive bred.

Karin knows a bit about their useful nature as a live food, I hope she'll post what she found?

[txg8gxp]

I know they have funny looking eyes :)

[tebstan]

How could I forget that!
Yes, they have cute little bug eyes that poke out to the side a bit. The eyes make them distinguishable from the freshwater ghost shrimp, if you look close.

They're supposed to get only about 2 inches when full grown, but are a little small this time of year. Maybe when they come in bigger in the spring I'll stand a better chance of keeping some as pets. Two inches might be just big enough to keep my angel away. Unfortunately, they don't have much of a life span, just over a year at best, half a year at worst.

[Europhyllia]

Yes I'll chime in.
I originally inquired with tebstan about them because I was afraid the freshwater shrimp would just die in my seahorse tank and foul the water. Little did I know that seahorses can eat 15 shrimp in under 5 minutes!

I still am going to prefer the saltwater grass shrimp over the freshwater ghost shrimp because according to my sources (seahorse.org and the octopus site -forgot the name) their nutritional make up is much superior as far as food for marine fish goes.
If you go with freshwater ghost shrimp you'd have to enrich them either by gutloading them or by injecting the stuff under their carapace. I don't have any desire or time to inject tiny shrimp!

The saltwater grass shrimp don't need to be enriched. They have a great balance of HUFE/EPA/DHA already. In fact on the octopus info I learned to expect a growth spurt with baby octopus once they start eating grass shrimp. Some seahorse sources also say that weight gain is better with grass shrimp than with mysis.

Speaking of Mysis: PE mysis don't need to be enriched because they already have plenty of HUFA and EPA but low on DHA so adding a live food like the grass shrimp should nicely balance that imbalance. :) (otherwise it can impact the ability to process certain nutrients)

That's all I know.

I fed the survivors some crushed sinking marine pellets that have spirulina in them. Hopefully they'll eat them. Not that they'll last long anyway but of course even if they're natural makeup is very favorable for marine predators (including seahorses!) if they get emaciated I'd assume their food value also goes down...

[hobogato]

i use to catch them at the coast when i had cuttlefish (the adult ones) a long time ago. i would keep them alive for more than a month on flake food and harvested macroalgae from the fuge.

[Europhyllia]

Ace how did you keep them?
Right now I just got a few left and they're in a 10 gallon aquarium with just an air stone.
I am guessing if I get bigger batches I should include some kind of filtration and hiding places?

They do eat the sinking pellets - they're no longer on the ground and the see-through shrimp have little green dots inside them ;)

[Europhyllia]

one more important piece of information: they're jumpers. Keep in a covered tank and when transporting them in a bowl, etc. cover them too.

[Europhyllia]

They breed as late as October, and can take up to 60 days to hatch, and need a bit of time to grow. They may not be available through the end of winter, as they are collected from the wild, not captive bred.

I wonder how long they live? Clearly I'll need to stock up. lol

[hobogato]

Ace how did you keep them?


i had a 20 gallon acrylic tank plumbed into another system. if you want to keep them long term, you have to give them something to hold onto. i use plastic gutter screen from lowe's.

[Europhyllia]

do you think a sponge filter would be sufficient? How many could I keep in a 10g?
Are they prone to being sucked up by a HOB?