Tired of FO

[Nitrate]

Since I got my LR for my 150 I am no longer satisfied with a FO tank. I got rid of a Stars and stripes puffer and a trigger so they wouldn’t destroy the rock, but still have some residents that are invert unfriendly.

What if any interesting critters could I add with the following fish?

Porcupine Puffer
Read Tailed Filefish
Volitan Lion
Cowfish
Naso tang
Dori
Frogfish
2 long spined urchins

I knew what the outcome would be, but I added a Horse shoe crab today, took about 2 seconds for the puffer to take notice and try to turn him over and it took the filefish almost 3 seconds to do the same. I moved him to my 20 (which is a whole different question, is a 20 with 25lbs lr enough room for a horse shoe to move around?)

I’m thinking a starfish of some sort, but I know next to nothing about inverts, so any advice would be appreciated.

 

[JG]

Horseshoe Crabs get very large ( adult 20 inches I believe). From what I've read about them, a tank usually does not provide enough food as they are sand sifters and therefor rarely make it long enough to reach adulthood.

They also like sandy bottoms and will spend much of their time under the sand. I'm not sure how they would get along in a cc bottom.