Bristlenose's pattern change

So, I'm pretty confident that it is nothing to worry about and it is most likely fully natural for a bristlenose but I would like to double check to be 100% sure.

This is a picture of my bristlenose normally;



My mum's tank has lost a great deal of fish which I believe is due to an Amonia or Nitrate spike. The bristlenose, one platy and the female betta seemed to have survived it, the only one out of the three that have any physical differences is the platy which has lost a fair bit of colour. I believe the betta and bristlenose have survived as they entered the tank a little bit before fish started dieing so I am hoping that they missed the spike. The inevitable happened in my sister's tank, a spike came and started killing fish. While I was over my dad's house, my mum took my sister's fish out of their tank and put them into the 180 litre which seems to have stabilized. The day that they entered, the pattern below started to appear. We have started to microwave the courgette for the bristlenose and he is all over it while it is in the tank and the pattern shows up again.

In the fish that were put into the tank, there was a male betta and he seems to flare up whenever the betta is near. I believe that the pattern may appear when the bristlenose either feels intimidated or angry. I am going with him being angry as the tank has gone from 3 fish to about 12-14. Do you think he may taken the whole tank has being his territory and is now ready to push the other fish away?

Any help would be appreciated, I'm thinking that I worry a little too much about him. xD

Looking at the blotchy coloration I would say that you still have Ammonia/Nitrite problems. Adding the fish from your sisters tank has probably caused another spike.

Have you done any water tests for Ammonia/Nitrites etc.
Have you done any water changes.
Are your fish showing any other symptoms, like rapid breathing.

He doesn't seem to have any increased breathing patterns and my mum currently does weekly water changes, the next is in a few hours.

My mum is also planning to get a better testing kit as the one she is using doesn't actually test for ammonia. This has all sort of turned out to be bit of a learning experience, I will not be making these mistakes with my tank.

I would also like to add that the pattern on the second picture comes on and off. When he is chilling on the side of the tank there is no pattern. When the male betta is near or he is eating, the pattern will appear again.

Your BN may be just showing signs of stress but given how many fish you've lost then I would assume it has been/still exposed to high levels of ammonia.

If you can get the test kits for ammonia and nitrite as soon as possible, as you need to monitor both these.

Your tank may have looked stable but adding 10 fish at one go is going to effect the bioload and your problems may well start again.

After your water change today I'd do daily water changes of 10% daily untill you have reading of zero for Ammonia and Nitrite. When this happens your nitrate will start rising and then weekly changes can be done.

Don't add any more fish untill then and when you do only add a few at a time.

Having test kits for all the major water parameters after that is a good idea, even if it's only the dip strips that are for 5 or 6 of the parameters.

agrred!

he should come good in a bit

So, I am back. After looking at my bristlenose for a while, I realised that the pattern he is coming up in is actually symetrical both sides.

We got an ammonia testing kit and an ammonia testing kit, the ammonia is showing as 0 while the nitrite is way over 30. I'm assuming I have measured it dead on a nitrite spike. This is worrying, I can't put him into my sister's tank as her tank is actually newer then the one he is. After testing her tank, I have found that her ammonia levels are through the roof so right now, we have two tanks, one of which is in the middle of a nitrite spike and the other is in the middle of an ammonia spike. His best chance will be in the nitrite tank right? I'll be ensuring that there are daily water changes to try and reduce the effect.

He does not seem to be gasping for air and is smashing his way through any courgette that I put in the bottom of the tank. Along with the algae wafers and algae from the tank, he seems to be eating well. I will be getting him some blood worm to try him on which he will be getting once a week.

All I can do is try to maintain the tank as well as possible and hope for the best. I am not one for using any formulas that supposedly reduce nitrite as I am worried about them damaging the fish.

Any extra advice any of you could give me to try and reduce the chance of him dieing?

a nitrate spike is dealt with by waterchanges he will be fine. Just be careful not to change too much water and sent the tank into a mini cycle

Ok thanks.

We are doing 10% water changes daily right now and I'm doing daily checks. Hoping for this nitrite to come down.

sounds good to me