Aquarium question! Any fish lovers know the answer to this?

Hello a couple questions,

I have a 4ft freshwater setup (3-4weeks old). I have 1 x red devil 1 x marble fenestratus and 1 x rivulatus and 1 x pleco. All about 10-15cm long.

My red devil has suddenly gotten very aggressive towards the other fish. My two other fish are both hiding behind fake plants to avoid the devil. My rivulatus is the same size and as the devil and even he is swimming away when he would usually stand up for himself. The devil is purposely pursuing my fish just to bully and chase them!

The devil is also digging holes in the gravel. Usually he/she is a big eater but this morning he would not eat at all (the other 2 ate fine).

My other question is about my pleco. I got him on Monday and he was doing fine to begin with. However the last two days he has not come out from under the wall. I have not seen him eat/suck since Wednesday. I have put cucumber in the tank (yesterday) as i know they love it. However, it has not been touched. I am just a little worried. I did a 40% water change yesterday as advised by vet nurse.

My levels are:
pH- 7.5-8
Nitrite- 0
Nitrate- 0
Carbon Hardness- 120
General Hardness- 60-120

What could be the issue? I don't want to get rid of my devil as he is just gorgeous but i don't know what choice i have if he continues to behave this way.

Have spoken to guy at fish shop where i bought them (he is a vet nurse). He says my levels are ok but should monitor behaviour over the next couple days.

Has anybody experienced this previously with their fish? I am also posting this on fish forums.

Please DO NOT reply if you are just going to whinge about people not knowing how to look after their pets. I am doing everything i am suppose to be doing and regularly asking the vet nurses' advice. Fish do strange things sometimes and everyone needs a helping hand and a little advice at some point.
By Curious24 8 years ago :: General
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