I think these are actually Satanoperca lucostica - Jurupari have face stripes and Lucostica have spots. But.... given the spots showing down the side flanks I am actually wondering if you have Satanoperca Mapiritensis - which do occasionally get imported under the wrong name.
Where did you get it from?
The important thing with these fish is very low nitrates, plenty of airation and very fine sand. I agree with Kittykat that a large tank is a must because of them doing best in groups I would go for it - in a 400, 5 or 6 would be a good size and just use your judgement as they grow. Not all of them will attain the largest size possible due to gender mixes, hierachy in a tank and also genes the odds of getting a group of 6 massive males would be unusual.
Low nitrates are the biggest thing for me when keeping Geophenes - they wont be exactly stressed in high nitrate but when something comes along that wants a way in they are not at 100% - additionally fine sand is a must as some decorative sands are actually quite large and can cause small grazes in the gill - again not good.
Geos and Satans are great fish though! And well worth meeting the needs for and if you can devote a show tank around them its just perfect and you will not be disapointed!
Wills
