Help on identifying cause of failed acclimation

[Evensong]

I'm stumped, and I hope someone can help me figure out what I've done wrong. I received 3 fish in the mail last week from a reputable seller -- a court jester goby, tailspot blenny, and white tail bristletooth tang. They were in transit for only about 18 hours (from the timestamp at the seller's UPS location to the time I picked them up at my local UPS store), and appeared to be in very good condition when they arrived. I float-acclimated the fish, following the seller's acclimation recommendations precisely.

After 30 minutes, the goby had disappeared and I haven't seen him since. I assumed he was just hiding, which would be normal. After about 10 hours, the tang started looking lethargic with his mouth open, but when I shut the room lights off he started swimming about the tank, so I took that as a good sign. In the morning however, the tang had died, and the blenny was clearly struggling. Still no sign of the goby. I quickly checked all of the parameters, which were as follows:
pH: 7.8 (Salifert)
Alk: 7.7 (Hanna)
Salinity: 1.023 (Milwaukee)
Calcium: 440 (Red Sea)
Phosphate: 0.22 (Hanna)
Nitrate: 6 (Red Sea)
Nitrite: 0 (Red Sea)
Ammonia: 0 (API)
Temp: 78F

So the pH and salinity are a little low, but I wouldn't think fatal. Phosphates are a little high. All parameters are stable.

I did a 10% water change to try to help gradually bring up the pH. The blenny didn't show much sign of improvement, but was still breathing (not eating) after 36 hours in the tank. But when I looked for him on the second morning, I was unable to find him. I've taken apart much of the rock work, blasted around with a turkey baster, checked the overflows and sump. No sign of the goby or blenny.

The tank completed its cycle back in early September, and I added 4 mollies (converted from fresh to saltwater) after that. I added live rock and sand from Gulf Live Rock in October, along with a frag of trumpet coral to serve as a barometer for changes in the parameters. After that, I added a cleanup crew of snails, hermits, and a conch. The mollies, coral, and crew are all doing very well today. The mollies had their first "litter" of babies earlier last week, and while of course not all of them survived, many of the fry are also doing well. I took that as an excellent sign that the tank was ready for more fish.

Some other details: it's a 120 gallon display with a 65g refugium and 18g sump, so the total system volume is around 200 gallons. I had to do some repairs on the 120, so the cycle was completed with just the refugium and sump. I added dry rock, dry sand, and some live rock to the display a week prior to adding the fish, and 120 gallons of freshly mixed water (Instant Ocean Reef Crystals and zero TDS RO/DI). The mollies and coral showed no ill effects to these additions, so I did not have any concerns with adding more fish. Clearly I missed something, though.

Any advice is welcome. Was I too hasty in adding that much dry rock to the system a week before introducing new fish (even though the existing fish and inverts were fine)? Should I have been more concerned about the pH or phosphates? Other things to test? How to try to prevent this in the future...? I had a tank for 2 years about a decade ago, and never lost a fish, so I'm in new territory here.

My current plan is to:
- Let the tank simmer for a while and just let the mollies live in luxury
- Add a fresh air line to the skimmer to bring the pH up, and see if I can get the phosphates down
- Very gradually convert over to Aquaforest Hybrid Pro salt.

Open to other ideas from the community.

 

[Kazumi]

I too had a tailspot blenny not survive shipping, they told me that some fish just don't take shipping very well. That order I also lost a Pajama Cardinal and a Chromis.

 

[Rp8]

Sorry for the loss. I know you float acclimated, but how did the fish first get wet with your water? Did you drip acclimate them in a separate container or just drop them in when they floated for a while?
If you just dumped them in that could have put them in shock. Even with a short trip in the bag, the water parameters change a lot.

 

[smitten with ocean life]

sorry about this. did you have plenty of water movement going? was the surface of the water being disturbed? you need good aeration

 

[Evensong]

Sorry for the loss. I know you float acclimated, but how did the fish first get wet with your water? Did you drip acclimate them in a separate container or just drop them in when they floated for a while?
If you just dumped them in that could have put them in shock. Even with a short trip in the bag, the water parameters change a lot.

I followed the seller's acclimation process exactly. Which was to float for 20-30 minutes with the lights off, release directly into the tank, and discard the bag water.

I assume you are correct that the salinity or other parameters were too different, and I should have given them a more gradual introduction.

 

[smitten with ocean life]

I followed the seller's acclimation process exactly. Which was to float for 20-30 minutes with the lights off, release directly into the tank, and discard the bag water.

I assume you are correct that the salinity or other parameters were too different, and I should have given them a more gradual introduction.

hmm. each seller has different recommendations, but that seems a little odd. usually you somehow slowly acclimate them to your water. like dumping them in a bucket and adding a bit of your tank water over a bit of time. not just floating them.

 

[Evensong]

sorry about this. did you have plenty of water movement going? was the surface of the water being disturbed? you need good aeration

You know, that might have contributed as well. My skimmer was producing a ton of microbubbles, and the tang was looking lethargic with his mouth wide open, so I switched the skimmer off for a while. Might've been the opposite of the smart thing to do...

 

[UncommonSense]

I wonder about equipment calibration issues? Salinity at 1.023 is low, but acceptable… unless it was actually lower?

 

[Evensong]

hmm. each seller has different recommendations, but that seems a little odd. usually you somehow slowly acclimate them to your water. like dumping them in a bucket and adding a bit of your tank water over a bit of time. not just floating them.

Yeah they were very clear to NOT use drip or air stone due to CO2 and ammonium accumulation in the bag water.

 

[Evensong]

I wonder about equipment calibration issues? Salinity at 1.023 is low, but acceptable… unless it was actually lower?

Another possibility. I'll pick up some calibration fluid, since I've only checked it with RO/DI previously.

 

[Boehmtown]

Lower salinity is easier for the fish. The warm and dump method is not great. Id definitely ease them into it. Fish can basically get stressed to death. You don't know that happened in that 18 hours

 

[Jarob]

Lower salinity is easier for the fish. The warm and dump method is not great. Id definitely ease them into it. Fish can basically get stressed to death. You don't know that happened in that 18 hours

That's the method Dr Reefs Affordable Aquaria and Biota both recommend. Float and dump, they specifically say do not acclimate other than temp.

 

[UncommonSense]

Another possibility. I'll pick up some calibration fluid, since I've only checked it with RO/DI previously.

Aah! Interestingly enough, Randy doesn’t recommend off the shelf salinity calibration fluid, as accuracy can be hit or miss! — I’ve experienced the same! (And, of course, RODI is way at the bottom of a salinity testers scale; so calibrating off this low end measurement can cause inaccuracies vs. calibrating at the target test measurement!)

— your best bet here for accuracy, if you have a relatively accurate scale, is making your own salinity calibration fluid!

Reef Aquarium Salinity: DIY Calibration Standards

Reef Aquarium Salinity: DIY Calibration Standards By Randy Holmes-Farley One of the most important issues facing marine aquarists is providing a suitable environment for their aquaria's inhabitants. Among the important properties for a marine...

www.reef2reef.com

Alternatively, it could be worth looking into a glass/crystal float Hydrometer! (Completely mechanical, sinks different amount at different SG… cannot come out of calibration if kept clean… Tropic Marin makes one that is well liked around here! [likely for its narrow resolution, specialized for testing saltwater, and not for generic brewing/etc!])

 

[Evensong]

Aah! Interestingly enough, Randy doesn’t recommend off the shelf salinity calibration fluid, as accuracy can be hit or miss! — I’ve experienced the same! (And, of course, RODI is way at the bottom of a salinity testers scale; so calibrating off this low end measurement can cause inaccuracies vs. calibrating at the target test measurement!)

— your best bet here for accuracy, if you have a relatively accurate scale, is making your own salinity calibration fluid!

Reef Aquarium Salinity: DIY Calibration Standards

Reef Aquarium Salinity: DIY Calibration Standards By Randy Holmes-Farley One of the most important issues facing marine aquarists is providing a suitable environment for their aquaria's inhabitants. Among the important properties for a marine...

www.reef2reef.com

Alternatively, it could be worth looking into a glass/crystal float Hydrometer! (Completely mechanical, sinks different amount at different SG… cannot come out of calibration if kept clean… Tropic Marin makes one that is well liked around here! [likely for its narrow resolution, specialized for testing saltwater, and not for generic brewing/etc!])

Holy cow that's a long article about making salinity calibration fluid

I think it would take less time for BRS to ship me the hydrometer than it'd take me to read and understand Randy's article lol

 

[Jarob]

Directly from Dr Reefs website, probably the most trusted fish retailer out there.

"Acclimation process for Fish​

• After receiving the package please inspect the box and bags for damage
• Please check all bags and make sure fish arrived alive.
• After checking, turn the aquarium lights off, then float all unopened bags in your sump or tank for temperature acclimation. Float for 20-30 min.
• After temp acclimation, cut open the bags and scoop out the livestock and release them in the tank or release all fish in a bucket along with transport water. Keep inverts separate as fish water may contain ammonia reducer. Then scoop the fish out of the buckets and release them in your tank.
• If fish were delayed in shipment, skip everything and simply release them in your tank right away, keeping lights off.

Low Salinity in some fish bags (For Fish Only)​

1. We generally ship fish at sg 1.023-26, in some fragile fish we do ship at much lower salinity at 1.018.
2. In case of low salinty, release all fish in a bucket, let them rest for 15 to 20 min for ambient air to interact with the water raising the pH slowly. After 15-20 pH should be balanced, then scoop them out and release in your tank keeping lights off. Do not worry about matching salinity.

DO NOT USE AIRSTONE/DRIP*​

*We do not recommend the drip method or use of airstone as it has a potential to hurt fish if not done properly and in quick time. When fish are bagged CO2 builds up in bags and causes the ammonia to convert to ammonium due to low pH. Ammonium is not toxic but once a bag is opened and O2 starts to interact with bag water specially with use of airstone, pH increases rapidly and so does ammonium converts back to ammonia, which is toxic. Thus please follow our acclimation method and not use drip or airstone."​

 

[RobertK]

Biota says the same thing:

Why shouldn't I drip acclimate your fish or add tank water to the shipping bag?​

Biota fish shipped directly from our facility are housed and shipped in full strength seawater. It's normal/expected for ammonium to build up in the shipping bag overnight. As the ammonium rises, the pH naturally drops. As pH drops, toxic ammonia is converted to the safer ammonium. We also use additives in the shipping water to convert toxic ammonia to ammonium. When you introduce higher pH tank water to the shipping water, that causes the pH to rise and also dilutes our additives, which causes the ammonium to convert back into toxic ammonia. It's much less stressful for a fish to have a small osmotic change than acute ammonia poisoning which can cause damage to sensitive gill tissue, tissue atrophy, appetite loss, and death within hours or days. If you drip acclimated or added tank water to the shipping bag already, prompt treatment with methylene blue can help relieve symptoms of ammonia poisoning in an emergency.

 

[Malcontent]

Ammonium is not toxic but once a bag is opened and O2 starts to interact with bag water specially with use of airstone, pH increases rapidly and so does ammonium converts back to ammonia, which is toxic. Thus please follow our acclimation method and not use drip or airstone."

How does oxygen from atmospheric air increase pH?

Aren't the fish bagged with pure oxygen?

 

[Jarob]

How does oxygen from atmospheric air increase pH?

Aren't the fish bagged with pure oxygen?

Couldn't tell you, just a copy and oast directly from their website.

 

[exnisstech]

Did you test the water the fish were shipped in? I always warm and drop shipped fish and usually local purchase as well but I always match salinty. I've seen fish come in as low as 1.015 and it's not at all uncommon to see 1.018 - 1.019.

 

[Evensong]

Did you test the water the fish were shipped in? I always warm and drop shipped fish and usually local purchase as well but I always match salinty. I've seen fish come in as low as 1.015 and it's not at all uncommon to see 1.018 - 1.019.

I did not, and I'm kicking myself for it because it would have really helped in identifying what went wrong.

In my previous tank, and so far in this tank, all of my fish came from a local seller where I knew the salinity, and I drip acclimated bc ammonia wasn't a concern. So this was the first time I was getting fish shipped to me overnight. Rookie mistake on my part to not have tested the bag water first.