Invertebrates only tank?

[crustaceanenthusiast88]

I’ve never had a saltwater tank, just fresh but I’ve always been fascinated with saltwater invertebrates like coral banded shrimp, arrow crabs, blue spiny lobsters, decorator crabs. I also really love starfish. Is it possible to have an invert only tank? And how small can I get away with going for? I know they say the bigger the tank the easiest, but how big do inverts need? Are they easier to care for than fish? Are all these things compatible?

 

[ISpeakForTheSeas]

Is it possible to have an invert only tank? And how small can I get away with going for? I know they say the bigger the tank the easiest, but how big do inverts need? Are they easier to care for than fish? Are all these things compatible?

Welcome to Reef2Reef!

Yes, it is possible. The tank size depends on the specific inverts, and a lot of people will have different opinions on what size of tank you'd need.

That said, for everything you listed except the lobster (which long-term would need an enormous tank), you could probably get away with a 40 gallon breeder tank, but obviously the bigger the better, and a lot of people would likely say that's too small for the arrow crab. Regardless, since most inverts don't swim, maximizing walking and climbing space in the tank would be suggested.

For the starfish, most starfish do not do well in our tanks.

Some people report moderate levels of success (i.e. where the star lives like 2+ years) with Chocolate Chip Starfish and with Goniaster tesselatus, but others don't have that much success with them. Very, very few people report any decent level of success with other stars like Linckias and Fromias. The only true starfish (Asteroidea) that I personally feel alright recommending for people to keep if they really want a starfish at this point are Aquilonastra stars (known in the hobby as "Asterina" stars) - they multiply fast enough to be considered pests, and some species under some circumstances may eat some corals like zoanthids, but they're cool, generally little stars. Otherwise, if it doesn't have to be a true starfish, I recommend Brittle/Serpent stars (Ophiuroidea), which typically do fine in our tanks.

The shrimp, arrow crab, and decorator crab would probably be compatible (though I'd ask if anyone has kept an arrow and decorator together before to be safe). I don't know for sure with the lobster, but I'd assume that one wouldn't be safe for the others (I haven't looked at lobster too intensively yet, but I have heard report of them eating snails, hermit crabs, and sometimes fish). Aquilonastra starfish would be fine with those, though, as would brittle stars (with the possible exception for the "Green Serpent Star," Ophiarachna incrassata, which is know to be predatory at least toward fish).

Some inverts (like Aquilonastra stars, a lot of snails, etc.) are easier to care for than most fish, others can be very difficult for one reason or another - regardless, a lot of inverts are much more sensitive to water quality than fish are, so good, stable water quality is important for them.

Edit: Ah, the comment below made me realize that I should point out - the inverts you mentioned wouldn't be difficult ones; just make sure you don't get copper or other toxins in the tank, maintain decent and relatively stable water quality, and they should do fine.

 

[Fish Fan]

Welcome to R2R!

I also really like the inverts like crabs and shrimps, etc. I say if those are the animals you want to try to keep, then go for it! There's a lot of cool critters you can keep in as little as a 10 or 20 gallon tank. And while you've obviously heard that larger tanks are easier to keep because they are more stable - and they are - if you're talking about crabs, most shrimp, hermits, snails, etc., these are typically very hardy animals and can do well in a smaller and less stable tank, in my opinion. Furthermore, they don't require more advanced monitoring of water parameters like corals do, and they don't need expensive or intense lighting like corals. An invert tank can be a very interesting and rewarding intro to saltwater aquariums, without being overwhelmed by the learning curve or need for expensive equipment. Take a look into setting up a FOWLR (Fish Only With Live Rock = tanks without corals). I know you don't want fish, but you could set up your invert tank up a lot like a FOWLR. In fact, you could setup a saltwater invert tank much the same way as one of your freshwater tanks.

Suggestion: if you like inverts, take a look at a Mantis, sometimes called a Mantis Shrimp, but they are not true shrimp. They are active, seemingly intelligent hunters with some of the most advanced eyes in the animal kingdom. Because they are aggressive, you really can't keep much else with them, but for some of us they are plenty cool all on their own.

Good luck with whatever you choose!

 

[EricR]

If you have specific inverts in mind that you really want, you'd have to research and consider which ones are compatible with each other, along with their needs.

If you wanted to just try it out and see how it goes, you could always do that and move forward if you decide it's worth upgrading:
-- PetCo has 20 gallon Aqueon glass aquarium for $27 right now,,, of course you'd need some equipment to go with it.
-- Chocolate chip star is cool/cheap/easy, in my opinion.
-- Throw in some hermit crabs, snails, etc and you're on your way.

*I only say that as someone who started with free jellyfish tank for a couple of years (not what you're talking about) and then started moving forward (tank transfers) as I got more interested with mostly inverts as my main focus as well

 

[EricR]

DELETE -- double post... sorry ,,, not sure how that happened

 

[crustaceanenthusiast88]

If you have specific inverts in mind that you really want, you'd have to research and consider which ones are compatible with each other, along with their needs.

If you wanted to just try it out and see how it goes, you could always do that and move forward if you decide it's worth upgrading:
-- PetCo has 20 gallon Aqueon glass aquarium for $27 right now,,, of course you'd need some equipment to go with it.
-- Chocolate chip star is cool/cheap/easy, in my opinion.
-- Throw in some hermit crabs, snails, etc and you're on your way.

*I only say that as someone who started with free jellyfish tank for a couple of years (not what you're talking about) and then started moving forward (tank transfers) as I got more interested with mostly inverts as my main focus as well

Thank you so much! I think starting with a starfish would be pretty cool!!

 

[crustaceanenthusiast88]

Welcome to R2R!

I also really like the inverts like crabs and shrimps, etc. I say if those are the animals you want to try to keep, then go for it! There's a lot of cool critters you can keep in as little as a 10 or 20 gallon tank. And while you've obviously heard that larger tanks are easier to keep because they are more stable - and they are - if you're talking about crabs, most shrimp, hermits, snails, etc., these are typically very hardy animals and can do well in a smaller and less stable tank, in my opinion. Furthermore, they don't require more advanced monitoring of water parameters like corals do, and they don't need expensive or intense lighting like corals. An invert tank can be a very interesting and rewarding intro to saltwater aquariums, without being overwhelmed by the learning curve or need for expensive equipment. Take a look into setting up a FOWLR (Fish Only With Live Rock = tanks without corals). I know you don't want fish, but you could set up your invert tank up a lot like a FOWLR. In fact, you could setup a saltwater invert tank much the same way as one of your freshwater tanks.

Suggestion: if you like inverts, take a look at a Mantis, sometimes called a Mantis Shrimp, but they are not true shrimp. They are active, seemingly intelligent hunters with some of the most advanced eyes in the animal kingdom. Because they are aggressive, you really can't keep much else with them, but for some of us they are plenty cool all on their own.

Good luck with whatever you choose!

Thank you so much for the advice! That makes me feel a lot better about wanting an invert tank, doesn’t seem as overwhelming now !!!