New tank help

[Overbrook]

I posted this over in emergencies but probably this isn’t as interesting as other things there. Anyway...trying here.
New biocube 32. Fishless cycle completed. Ammonia 0/ Nitrite 0/ Nitrate 5-10 (10 on API, 5 on salifert)/ PH 8.0 /dKH 7.6/ Salinity 1.025.
Initially using tropic marin pro but that's become harder to get and my last water change (50%) was done with IO (not reef crystal).
Purchased a (super) small royal gramma online which arrived this am. Pretty quiet in the bag, hiding in the corner and not moving much but would swim a little when I slowly inverted the bag. This is my first online fish so I'm not sure how much action there should be. Followed the acclimatization process on that was recommended (floating bag, 1/2 cup every 4 In). After about an hour let the fish in and it promptly swam to a low flow corner, laid down and was breathing fast. Dead in 1 hour.

I'm kicking myself that I jumped the gun on ordering the fish with a bit of nitrate in the tank. Would a nitrate of 5ish (or the relatively low dKH) really kill a fish that quick? Did I acclimate too fast (I'm sure the dKH was higher in the bag)? I don't want to simply blame the company (the fish was still mostly alive when I opened the box and all). I'd love to hear thoughts on what anyone would do next. My current plan is to completely switch over to Red Sea Coral pro (and ultimately their system) and then try again when everything looks good (absolutely zero nitrate and a less borderline dKH).

Thanks!

 

[Raege]

Don’t kick yourself on this one. Nitrates not an issue sounds like fish was stressed in shipping and or had an issue already that it just couldn’t overcome. Did you note any marks dots film on skin anything that you wouldn’t see on a sales pick for the fish?

 

[redfishbluefish]

Not sure cycle is done. How old is the tank? Did you add ammonia to see if it quickly converts? Did you use truly live rock (not white "dead" live rock)? Did you use a bottled bacteria.... Just because you have nitrate doesn't mean cycle is done. That nitrate could have easily come for leaching out of the rock and not from ammonia->nitrite->nitrate conversion. Ammonia is highly toxic to fish, and that's my guess in what killed it.....sorry for your loss.

 

[Scotty Buttons]

The nitrate wouldn't of killed the fish. I would double check your ammonia with something besides API. Grammas are pretty hardy. But it's possible it was sick when it arrived and the stress from shipping finished it off

 

[Raege]

On the salt I use TM bio active for peace of mind but started with it. Salt choice if it mixes to what you like DKH etc or you are fine dosing to match your tank water should be fine. There are threads where it been pointed at one brand of batch caused issued but many users of said branch never had issues so inconclusive to me. Check your mixing barrel if it’s clean and ya line the parameters to k it

 

[Crustaceon]

Sounds like shock due to acclimating too fast. I like to drip acclimate in a little bucket for an hour at two drips per second, preferably close to the tank to keep the temperature close to where it should be. It tends to triple the water volume in the bucket. I then put the fish + water back into the bag and float it for twenty minutes to fully temperature acclimate.

 

[Overbrook]

Thanks so much for the comments. I just broke out the salifert ammonia test and it read 0 as well as the API. I cycled with BioSpira using and the tank was set up with life rock (30ish pounds) and Carib Sea Fiji pink (20 pounds). If the ammonia, dKH, or nitrate didn't do it is, are there any possibilities other than a bad acclimation? What parameter is the fish acclimating to?