What are some very cool marine aquarium animals?

[Mr. Seahorse]

In a small biotope with no exposed power heads, low flow, without wrasses, and with a huge supply of bryopsis

That's basically my tank

 

[SupraSaltyReefer]

Christmas tree worm rock is one of the coolest inverts, but it’ll be hard for you to keep the porites alive in a 20g.

 

[tribbitt]

Christmas tree worm rock is one of the coolest inverts, but it’ll be hard for you to keep the porites alive in a 20g.

Porites is pretty hardy so it might stick around. However the worms will appreciate extra feeding occasionally

Jake Adams had a great christmas tree worm tank

 

[Darkxerox]

Christmas tree worm rock is one of the coolest inverts, but it’ll be hard for you to keep the porites alive in a 20g.

This I've actually done in a 12g tank. You do need to have strong lighting for the porites (mine was getting about 250 PPFD) and enough food in the water column for the worms (actually the hardest thing without polluting). When I went fishless, I needed to add oyster eggs and phyto to keep the worms alive and growing.

 

[BAYMAC]

They used to be one of those impossible to keep animals (and still kinda are along with tunicates, horseshoe crabs, many sea star species, lettuce nudibranchs, coco worms, sea apples, colder water inverts, etc.). However @Srt4eric has managed to keep one alive somehow. I told him it was from all the plumbing "residue" on his arms from work

But don't get one unless you enjoy watching things die however. Stick to hardy, well-documented species that people have kept successfully and don't encourage stores to keep buying things that die easily by spending your money on them.

Their lifespan isn't that long and we typically get them at larger sizes.

 

[BAYMAC]

This I've actually done in a 12g tank. You do need to have strong lighting for the porites (mine was getting about 250 PPFD) and enough food in the water column for the worms (actually the hardest thing without polluting). When I went fishless, I needed to add oyster eggs and phyto to keep the worms alive and growing.

When I was at RN, I kept a thriving colony for years. I fed the crap out of it lol

 

[Mr. Seahorse]

I'm definitely not getting a Yellow Sea cucumber because it can nuke a tank. But I appreciate all the replies and good ideas!

 

[BAYMAC]

I'm definitely not getting a Yellow Sea cucumber because it can nuke a tank. But I appreciate all the replies and good ideas!

The yellows are small, and don't really nuke tanks, they're not like the sand sifters. They're a fine addition if you feed them.

I have never seen them puke their guts and I have handled thousands!

 

[BAYMAC]

Never head of them but looks really cool. I would love one.

They only come from the Sea of Cortez, and they don't always ship due to Mexican politics. Awesome creature, but if they can get snagged on debris, they don't do so well.

 

[PjFish]

 

[Mr. Seahorse]

Brine shrimp!!!!!!!!!! Memorys...........

 

[PjFish]

And stated " They can even be trained'
Mine never got to 3/4 as advertised!!

 

[Mr. Seahorse]

" They can even be trained'

The company has great false advertising!!!
I have grown brine shrimp to 1.25 inches long!