Gold Severums

Question
QUESTION: I have two Gold Severums, both about 15 months old. Until now, they have been peaceful toward other fish, but lately they have become aggressive, attacking any passerby fish. I have also noticed that their both dropping gravel in front of the tank, and slowly building themselves a wall. Is this a territorial thing? They both lost their appetites, and one of them shudders quite frequently during the whole day. Could you tell me what's happening to them, and if building walls is normal behaviour?

ANSWER: Hi Chris,
 They are either preparing to lay eggs, or already have.  
Have they gone darker (i.e., more contrasty in color)?

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>


---------- FOLLOW-UP ----------

QUESTION: I haven't noticed any difference. Last week, I got concerned because they started to rub themselves against the rocks and gravel and then the shuddering started. My local fish supplier told me that it could be condition of the water causing an irritation, but I did a test and everything seemed ok. PH was 7.2. Ammonia and nitrite levels were low. However, the nitrate levels were quite high but not critical. He then told me on Friday to use medicine for gill flukes, which I'm using right now. It wasn't until next day that I noticed all the gravel were building up in front of the aquarium glass. The Severums started attacking the angelfish and clown loaches. They even attacked the plants and pulled them out of the gravel and moved it in front of the tank. It was such unusual behaviour. If they have laid eggs, I can't find them.

Answer
Hi Chris,
  I wouldn't trust that pet store very much and I would stop treating for gill flukes.  They are showing perfect signs of a pair that is nesting.  They clear the plants away from the nesting area to make it harder for small fish to sneak up on the nest.  I have seen this a lot both in tanks and in the wild (not with severums per se, but with dozens of other species -- this is very typical nesting behavior).  

 You may want to keep an eye on the rest of the fish in the tank and possibly have a plan B for putting them someplace. Severums are excellent parents and that often means making sure that nothing else can harm their kids.

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>