Hermit only tank -HELP! HIGH ammonia!

[hermitOG]

Ok so we brought hermit crabs home from the beach and decided to keep them. I did a bunch of googling and ran to get what equipment I could. This was probably over a month ago now and everything has been fine until a day or two ago when the ammonia started testing super high - over 8.0. Is it just cycling? Will it kill the hermits? How do I keep that from happening?
Background:
I have a 10 gallon top fin aquarium kit with just the filter that came with it (I think this is probably unnecessary in a SW tank? But I leave it anyway - good to keep water moving?) I have I think about 7 lbs of live rock from petco, 10 lbs of live sand and the water is straight from the ocean we found them in. I’ve been feeding them a whole cube of frozen brine shrimp every night. Too much? There were 12 hermits in all, 5 of them large. 2 if the large ones have died in the last week (1 after he molted and I think was moved around and messed with too much and the other may either have been killed for his shell or died because he was trying to molt and couldn’t find another good shell - I do have several empty shells lying around. All of the crabs have changed shells multiple times) the first one I didn’t know had died for several days as he was just hiding after his molt for several days anyway. When I realized he was dead he was already starting to fall apart and smelled HORRIBLE. I removed the 2nd dead one much faster but he was still in there for a day or day and half. I put some ammonia remover in and did a 10% water change tonight after tested the water to find the ammonia so high. I tested again after and it didn’t seem to be any different. I have not fed them today and won’t. What else should I do?

 

[WV Reefer]

Ok so we brought hermit crabs home from the beach and decided to keep them. I did a bunch of googling and ran to get what equipment I could. This was probably over a month ago now and everything has been fine until a day or two ago when the ammonia started testing super high - over 8.0. Is it just cycling? Will it kill the hermits? How do I keep that from happening?
Background:
I have a 10 gallon top fin aquarium kit with just the filter that came with it (I think this is probably unnecessary in a SW tank? But I leave it anyway - good to keep water moving?) I have I think about 7 lbs of live rock from petco, 10 lbs of live sand and the water is straight from the ocean we found them in. I’ve been feeding them a whole cube of frozen brine shrimp every night. Too much? There were 12 hermits in all, 5 of them large. 2 if the large ones have died in the last week (1 after he molted and I think was moved around and messed with too much and the other may either have been killed for his shell or died because he was trying to molt and couldn’t find another good shell - I do have several empty shells lying around. All of the crabs have changed shells multiple times) the first one I didn’t know had died for several days as he was just hiding after his molt for several days anyway. When I realized he was dead he was already starting to fall apart and smelled HORRIBLE. I removed the 2nd dead one much faster but he was still in there for a day or day and half. I put some ammonia remover in and did a 10% water change tonight after tested the water to find the ammonia so high. I tested again after and it didn’t seem to be any different. I have not fed them today and won’t. What else should I do?

What kind of hermits are these? Terrestrial or Aquatic? Any pics?

 

[hermitOG]

Yes aquatic. We found them in the surf in the gulf. I can’t seem to figure out how to post a pic with my phone...

 

[hermitOG]

They are aquatic. We found them in the surf in the gulf. You can see the 3 big ones. The small ones are mostly buried.

 

[hermitOG]

I might add I’d like to turn it into a reef tank adding some fish and corals eventually, but obviously im a ways away from that. If possible I’d like to keep the crabs alive in the meantime. Can I successfully complete the cycle and get it set up properly with the crabs still in there? Thank you for any tips.

 

[hermitOG]

I might add I’d like to turn it into a reef tank adding some fish and corals eventually, but obviously im a ways away from that. If possible I’d like to keep the crabs alive in the meantime. Can I successfully complete the cycle and get it set up properly with the crabs still in there? Thank you for any tips.

 

[WV Reefer]

I might add I’d like to turn it into a reef tank adding some fish and corals eventually, but obviously im a ways away from that. If possible I’d like to keep the crabs alive in the meantime. Can I successfully complete the cycle and get it set up properly with the crabs still in there? Thank you for any tips.

The main thing is get that ammonia down.

It could have had a large spike because of the dead body.

 

[hermitOG]

What’s the best way to do that with them in there? Water changes everyday?

 

[WV Reefer]

I would do a series of small changes until you see the levels drop.

With live rock you shouldn’t have had that large of a spike that’s why I think it was the dead bodies.

If you can just keep the ammonia down you will be good to go.

 

[hermitOG]

I would do a series of small changes until you see the levels drop.

With live rock you shouldn’t have had that large of a spike that’s why I think it was the dead bodies.

If you can just keep the ammonia down you will be good to go.

Alright, thanks! I’ll do that. Am I feeding them too much? I see dead shrimp in the sand and floating around all the time. Should I cease feeding til it goes down?

 

[WV Reefer]

Alright, thanks! I’ll do that. Am I feeding them too much? I see dead shrimp in the sand and floating around all the time. Should I cease feeding til it goes down?

Yeah that’s way too much. It may be that you are polluting the water. Only give them what they can grab within a minute or so.

 

[hermitOG]

Yeah that’s way too much. It may be that you are polluting the water. Only give them what they can grab within a minute or so.

Ok thanks! They don’t generally try to grab it while I’m feeding them so I didn’t know how much to leave for them to find later.

I just did another water change and tested again and the ammonia looks to be down around .5! Nitrites and nitrates are still high, 10 and 160 respectively. I assume those will go down next? Looks like the alkalinity and ph are also low now. Maybe I should start mixing my own water and stop using the gulf water.

Thanks for all your help!