Quick I was trying to catch ghost shrimp for fishing and I took them home in a livewell and they had babies...

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Amethyst

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I found this image online, but this is literally identical to the crab I have in the tank currently. Can you tell me if I can keep Stone crabs or ama crabs (aka rock crabs) the same way?
 

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I found this image online, but this is literally identical to the crab I have in the tank currently. Can you tell me if I can keep Stone crabs or ama crabs (aka rock crabs) the same way?
To my knowledge, Stone Crabs (Menippe. spp.) and A'ama Crabs (Grapsus tenuicrustatus) are both tropical crabs, and would die at these lower temps. Also, as a note here, Dungeness Crabs, Stone Crabs, and A'ama Crabs are all predatory species, and they may eat your shrimp once they get big enough. All of them would also outgrow a 10 gallon tank in time, and they will probably all need bigger foods than your shrimp - I'd suggest going with some larger pellets to feed any crabs (the TDO Chroma Boost brand has larger pellet sizes, and - to my admittedly limited knowledge - they should all work).

So, these crabs would be better in a separate tank for the shrimp's safety, and they'll need different, larger feeds.
 
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To my knowledge, Stone Crabs (Menippe. spp.) and A'ama Crabs (Grapsus tenuicrustatus) are both tropical crabs, and would die at these lower temps. Also, as a note here, Dungeness Crabs, Stone Crabs, and A'ama Crabs are all predatory species, and they may eat your shrimp once they get big enough. All of them would also outgrow a 10 gallon tank in time, and they will probably all need bigger foods than your shrimp - I'd suggest going with some larger pellets to feed any crabs (the TDO Chroma Boost brand has larger pellet sizes, and - to my admittedly limited knowledge - they should all work).

So, these crabs would be better in a separate tank for the shrimp's safety, and they'll need different, larger feeds.
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I was told red rock crabs are the same as stone crabs and this is what I am talking about, am I correct?

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and I call the crabs I see in the rocks ama crabs because they are identical to ama crabs but I have only seen pictures from them in Hawaii.

also, I only plan to keep them together as babies (1- 3 inches) is that still ok?
 
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3 more questions plus update. we just ordered TDO chroma boost size small C2, do you think that will be fine for them?
And we have been feeding them ground up TetraMin tropical flakes and ground up-freeze dried blood worms, is that an okay food for them? And also I am planning on catching and adding a small smelt, like 2-4 inch smelt, do I feed them the same?
 

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I was told red rock crabs are the same as stone crabs and this is what I am talking about, am I correct?
This is the hard thing with common names - they probably are the same thing to some people, but not to others. From what I’ve seen, these two crabs are different. The Red Rock Crab (at least the one in your picture above) is Cancer productus, while Stone Crabs (as mentioned) are Menippe spp. Cancer productus prefers slightly colder water (~46-54F), but - temperature-wise - you could keep it and the shrimp at 53F and still probably be in their ideal range.
I call the crabs I see in the rocks ama crabs because they are identical to ama crabs but I have only seen pictures from them in Hawaii.
Do these crabs by chance look like the Striped Shore Crab, Pachygrapsus crassipes? If so, there’s not really a known temperature range for them - the only listed maximum I found stated 73F was the max they can tolerate, and the only other info I could find was an increase in larvae of these guys when the temp rose above 50F. So, with that in mind and looking at some of the places where these guys are found, I’d guess their ideal temperature range is somewhere between 50-62F. Again, you could probably keep these guys at 53F without issues (they may prefer slightly warmer, but I’m not sure).
also, I only plan to keep them together as babies (1- 3 inches) is that still ok?
I honestly don’t know - it really just depends on when the crabs get big enough to prey on your shrimp, and if they decide to do so. I have no experience keeping crabs and haven’t looked into it much because crabs aren’t considered reef safe, so I don’t know where that line would be - hopefully someone here with more hands on experience with crabs will be able to give you an idea in that regard.
 
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This is the hard thing with common names - they probably are the same thing to some people, but not to others. From what I’ve seen, these two crabs are different. The Red Rock Crab (at least the one in your picture above) is Cancer productus, while Stone Crabs (as mentioned) are Menippe spp. Cancer productus prefers slightly colder water (~46-54F), but - temperature-wise - you could keep it and the shrimp at 53F and still probably be in their ideal range.
Yeah that is what I thought and is what I saw online, Cancer productus.
Do these crabs by chance look like the Striped Shore Crab, Pachygrapsus crassipes?
Exactly, that is exactly what I have here!
3 more questions plus update. we just ordered TDO chroma boost size small C2, do you think that will be fine for them?
And we have been feeding them ground up TetraMin tropical flakes and ground up-freeze dried blood worms, is that an okay food for them? And also I am planning on catching and adding a small smelt, like 2-4 inch smelt, do I feed them the same?
also are you able to answer these?
 

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I believe smelt are a shoaling fish, so you should leave those alone, as you don't really have the space for a proper shoal.

The food you're describing is fine for crabs and scavenging shrimp, yes.
 
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I believe smelt are a shoaling fish, so you should leave those alone, as you don't really have the space for a proper shoal.

The food you're describing is fine for crabs and scavenging shrimp, yes.
wat dat mean
 

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Yeah that is what I thought and is what I saw online, Cancer productus.

Exactly, that is exactly what I have here!

also are you able to answer these?
Yes, sorry - got distracted and forgot to answer those.

I’m guessing the Small will work for them (it would make sense to me that they could eat larger pellets than the type-A based on what the larvae eat, and the Small is still within the the range of coarse sand, so it should work) - let me know how it goes!

Yeah, as mentioned, the flakes and bloodworms should be fine - the main things to look for in foods are the ingredients and (arguably more importantly in most cases) the guaranteed analysis (which you should always calculate the dry matter basis of the analysi, which I discuss how to do in the quote* below). Generally speaking, with marine foods you typically want high protein and low to moderate fat - LRS Reef Frenzy (or LRS Fertility Frenzy) is probably the best food on the market by ingredients and guaranteed analysis, with ~63% protein and ~14% fat, but basically anything with decent ingredients, 50% or more protein, and 10-15% fat should be good enough as a staple diet for most animals (in this case, the tropical flakes are a tiny bit low on protein at 49%, but the bloodworms make up for that).

Smelt is another case of common name confusion. Freshwater or Typical Smelts (which actually mostly live in the ocean) are fish in the order "Osmeriformes", while Marine Smelts are in the order "Argentiniformes", so the term “Smelt” is actually applied to huge number of fish species. That said, as was stated above, smelt are typically shoaling fish (meaning they form little groups that stick together when they move about - it’s similar but slightly different than a schooling fish; the link below explains it better**), so they may do best in groups (some shoaling fish do, some don’t in our aquariums). Either way, most smelt that I’m aware of would grow far too big for a 10 gallon tank (4 inches would probably be too big as is if the fish is decently active), and smelt are also planktivorous, meaning they eat zooplankton (like pods). A commonly kept species in the hobby with a similar diet is the Mandarinfish, Synchiropus splendidus, and to meet their dietary needs without having to add pods every day (or multiple times a day) it is recommended to have a 40 gallon tank with plenty of space (typically meaning lots of rocks) where pods can breed freely and safely in the tank for some time before the mandarin is added to the tank. So, long story short, you would feed them a ton of pods, and smelt would probably not be a good addition for your tank at this point.

*The Dry Matter Basis calculation quote:
With regards to the moisture and protein content, when looking at foods for pets (fish, cats, dogs, etc.), it's a good idea to look at the dry matter basis of the guaranteed analysis. To state it simply, frozen foods and wet foods show super low protein and fat contents on their guaranteed analysis labels when compared to dry foods - this isn't because they're lower quality or less healthy, it's just that they have more moisture in the mix. To compare apples to apples protein and fat of frozen/wet vs dry foods, you take the dry matter basis of each factor (protein on its own and fat on its own once you've accounted for moisture).

For example, San Francisco Bay Brand Frozen Spirulina Brine Shrimp lists the following guaranteed analysis:
Crude Protein (Min): 3.7%
Crude Fat (Min): 1.2%
Crude Fiber (Max): 1.6%
Moisture (Max): 94.8%
Ash (Max): 0.2%
Phosphorus (Min): 0.1%

Looks very not nutritious. But, when you account for the moisture by taking the dry matter basis, you realize that that 3.7% protein is 3.7 out of 5.2 (the actual amount of food in the pack; i.e. the percent of the food that isn't moisture like the water used to hold the frozen food together or to keep the meat in the cat food can fresh). So, looking at the dry matter basis, 3.7/5.2 = 0.71 (rounded for simplicity's sake) - times this by 100 to get the percentage and you get a dry matter basis of 71% Crude Protein content. So, while it looks unhealthy at first glance, when you look at just the food in the food packet and not the moisture plus the food, you find out that the food is actually fairly healthy.

Because of this, a lot of frozen/wet pet foods look worthless at first glance, but some of them are actually top of the line foods when compared to dry foods this way. The only real downside of frozen/wet foods is that - because of the high moisture content - you might not always be getting as much food pound for pound as buying dry (i.e. one lb of dry food is going to have a lot more actual food in the container than one lb of frozen/wet food because of the lower moisture content). This really just means that frozen/wet foods are generally more expensive.

TLDR: Frozen/wet pet foods look unhealthy, but, accounting for moisture, they're usually high quality. They're just expensive too.
**The website that explains the difference between shoaling and schooling better:
 

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TLDR summary of the above: the small should work, let me know if it doesn’t. The food you’re feeding should be just fine as long as they’re eating it. Smelt eat pods - lots of pods - and are a probably a bad idea for your tank (they would be probably be super stressed and die either from stress or from not having enough pods to eat).
 
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Yes, sorry - got distracted and forgot to answer those.

I’m guessing the Small will work for them (it would make sense to me that they could eat larger pellets than the type-A based on what the larvae eat, and the Small is still within the the range of coarse sand, so it should work) - let me know how it goes!

Yeah, as mentioned, the flakes and bloodworms should be fine - the main things to look for in foods are the ingredients and (arguably more importantly in most cases) the guaranteed analysis (which you should always calculate the dry matter basis of the analysi, which I discuss how to do in the quote* below). Generally speaking, with marine foods you typically want high protein and low to moderate fat - LRS Reef Frenzy (or LRS Fertility Frenzy) is probably the best food on the market by ingredients and guaranteed analysis, with ~63% protein and ~14% fat, but basically anything with decent ingredients, 50% or more protein, and 10-15% fat should be good enough as a staple diet for most animals (in this case, the tropical flakes are a tiny bit low on protein at 49%, but the bloodworms make up for that).

Smelt is another case of common name confusion. Freshwater or Typical Smelts (which actually mostly live in the ocean) are fish in the order "Osmeriformes", while Marine Smelts are in the order "Argentiniformes", so the term “Smelt” is actually applied to huge number of fish species. That said, as was stated above, smelt are typically shoaling fish (meaning they form little groups that stick together when they move about - it’s similar but slightly different than a schooling fish; the link below explains it better**), so they may do best in groups (some shoaling fish do, some don’t in our aquariums). Either way, most smelt that I’m aware of would grow far too big for a 10 gallon tank (4 inches would probably be too big as is if the fish is decently active), and smelt are also planktivorous, meaning they eat zooplankton (like pods). A commonly kept species in the hobby with a similar diet is the Mandarinfish, Synchiropus splendidus, and to meet their dietary needs without having to add pods every day (or multiple times a day) it is recommended to have a 40 gallon tank with plenty of space (typically meaning lots of rocks) where pods can breed freely and safely in the tank for some time before the mandarin is added to the tank. So, long story short, you would feed them a ton of pods, and smelt would probably not be a good addition for your tank at this point.

*The Dry Matter Basis calculation quote:

**The website that explains the difference between shoaling and schooling better:
Yeah one time I tried to keep smelt in a 5 gallon bucket live well for fishing so I didn't have to catch them every time and they only survived 2 weeks, I wondered why they died but I didn't realize it was too small of an enclosure for them
 

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The smelt in that bucket died because they weren't in a cycled tank. The small size is bad for their long-term happiness, not necessarily for their physical health.

"Shoaling" means a fish that lives in groups. If you keep a shoaling fish alone, it'll be stressed.

If the food is like dust in the water, it's too small. You need to give the shrimp and crabs pieces of food that they can actually hold in their claws and eat. Turn off the pumps, and use tongs or a turkey baster to put the food directly by them. Then you can see if they start eating.
 

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If the food is like dust in the water, it's too small. You need to give the shrimp and crabs pieces of food that they can actually hold in their claws and eat. Turn off the pumps, and use tongs or a turkey baster to put the food directly by them. Then you can see if they start eating.
This is true for most shrimp and crabs, but not for these guys:
"They feed on detritus filtered from the water and sifted from the substrate by the hairs on their second and third legs."*
So, while these guys likely can eat bigger foods (probably up to about 4mm or so), they actually typically eat smaller foods in the wild.
How do I tell if they eat the food when it is like dust in the water
Short of a camera with a very high quality zoom, I'm honestly not sure what the easiest method would be. My suggestion would be to take a wide, shallow cup of sand and mix some of the food in with it, then set it across the tank from the shrimp and see if they go to start digging through it. If they do, then observe them as they dig and see if they bring their second and/or third legs up to their mouths repeatedly as they dig. (The video linked below** shows one feeding as it digs and crawls around, so you can use it as a reference to give you an idea of if it's eating or not.)

Yeah, being in a too small, uncycled tank, likely without a proper food source is basically guaranteed to kill the fish - live and learn. Stress won't kill something right away in our tanks, but it will almost always contribute to it dying prematurely (it increases the likelihood of disease, aggression, jumping out of the tank, injuries, etc.).

*Source:
**The video:
 
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Short of a camera with a very high quality zoom, I'm honestly not sure what the easiest method would be. My suggestion would be to take a wide, shallow cup of sand and mix some of the food in with it, then set it across the tank from the shrimp and see if they go to start digging through it. If they do, then observe them as they dig and see if they bring their second and/or third legs up to their mouths repeatedly as they dig. (The video linked below** shows one feeding as it digs and crawls around, so you can use it as a reference to give you an idea of if it's eating or not.)
Yeah that is what they have been doing before I started feeding them. Also sometimes with their big moustache they put it to the ground and go forward collecting sand in it like a bull dozer and it was all in the shrimps big moustache because they have that
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and I don't know why they did that. My guess is it was collecting food
 

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Yeah that is what they have been doing before I started feeding them. Also sometimes with their big moustache they put it to the ground and go forward collecting sand in it like a bull dozer and it was all in the shrimps big moustache because they have that
1669397029721.png
and I don't know why they did that. My guess is it was collecting food
That would be my guess too - looking for food in the sand.
 
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I found a weird tiny fish at the beach and it is like an inch and a half and it has faint yellow stripes and a red tail and I think it has big eyes and I literally don't know what it is, it likes ham.
 
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Any pics of it?
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These are some pictures I took with my phone because I lost my gopro, my phone was submerged a few weeks prior so the color is a little weird and it is a little more foggy. The only thing to know is the fins are more red than in the picture and the colors are less dull than in the picture.
 
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