Yellow Tangs

[Karakeys]

Hi ive a 150 us gall tank perfect water conditions for a considerable time and definately not overstocked. 2 wreck fish, 1 (3 inch) emp angle, 1 (3 inch) rock beauty, 2 scooter blennies, 1 fire fish, 1 (3 inch) regal tang, 1 (1.5 inch) percula clown, 1 1.5 inch watchman gobie, 1 bloodshrimp, 1 cleaner shrimp, 1 pistol shrimp. 2 atlantic anenomes, bout 12 hermies and bout 12 turbo snails. Maybe due to halides being on too long developed a bit of a hair algae overgrowth and having wanted some yellow tangs for a while read up on them. Advice was 1 or 6. Didnt want 1 so I bought 6. Day 2 one died then day 3 another died. My ammonia rose to 0.25% and I carried out 2 10% water changes a day till this stabilised. It took about 5 days. Ive since replaced the tangs and things are now stable. I have learned a hard and expensive lesson. The expense being the least of how this has affected me. Im devastated that the fish died and even adding ammonia detox to the tank couldnt save them. I also noted that the water temp was 83 ive since reduced this to 78 - could this have added to the problem.

ps ive just checked the water again and the ammonia is zero but my pH has risen from 8.4 to 8.8

 

[Navarre]

When you have a low stocked tank for a long period of time then add a large quantity of fish, you are immediately putting tremendous stress on the bacteria. Lets consider you have 5 fish and then add another 5 fish, you are effectively adding 200% of the waste products that the bacteria is able to cope with so a cycle will happen and thus cause stress.

If you have a heavy stocked tank of lets say 20 fish and then add 5 more then you have an increase of only 20% of the waste products.

Now dont get me wrong, this doesnt mean you can continue to add more and more fish to make it very heavily stocked, even the bacteria only has a finite surface area which to colonise. You can however easily upset and make the tank unstalbe by adding large quantities of fish to a system that has low stocking levels.

 

[fraservet]

yep, too much too quickly I'm afraid.
thankfully your reasonably big water volume would have reduced the impact of the excess ammonia etc. otherwise you could have had even worse problems.

By the way, good luck with the yellow tangs and hair algae!

Bristletooth are the best tangs for that iirc.

Not sure about the cause of the pH rise - possibly the ammonia remover could be responsible?