Apistogramma caucatuoides compatability

Question
QUESTION: I am about to switch my tank set-up. I have a 3.5 inch Kenyi and a 3 inch Auratus in a 38-gallon tank and it is getting to the point where the Kenyi is bullying the Auratus and the Auratus won't fight back. I know the tank is too small and that is why I am trying to get rid of the two fish I have. I did not find out how aggressive those two cichlids were until after I bought them. I bought them at Wal-Mart and they did not have info on them and they had them in a "mixed cichlid" tank. Anyways, I was planning on getting the new set-up going before adding any fish once I get rid of the fish I have and I was wondering how much the stuff that I put into my tank will lower the pH? I am going to have either sand or pea gravel or both as a substrate and I will have a piece of drift wood in the center of the tank plus a broken 6.5 inch clay pot will form caves across the floor of the tank. I will also have live plants in the tank (Indian Red Sword plant, Java Fern, Elodea, and eventually I might have a Java Moss wall). I also have a bubble disk and a bubble wall that I can put into the tank if it won't hurt the fish to have that much aeration or water movement. The filter that I am running on the tank is an Emporer 400. When I do set up the tank do you have any suggestions for fish that would go well with Apistogramma Caucatuoides? I am looking for fish from the same region as the Caucatuoides (Columbia) and ones that are just as pretty or more pretty than the Caucatuoides. They would also have to be compatible with the Caucatuoides. Thanks in advance for your help.

ANSWER: Hi Thomas:  A lot of the pH issue will depend on what kind of sand or gravel you put into the tank.  Silica sand and coral sand/gravel will raise pH... Driftwood will lower it. As for the compatibility of cichlids with the Apistogramma Caucatuoides most of the dwarf cichlids would work... with perhaps the exception of the Ram... dave

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QUESTION: Would the live plants raise or lower the pH? Would play sand (the kind you put into a kids sand box) or pea gravel (the kind made mostly out of quartz) raise or lower the pH? The water comes out of the faucet here at 7.0-7.2 pH. Would the Emperor 400 filter create too much of a current for the Caucatuoides? How about for Blue Rams? I want a fish that I can put in the 38-gallon tank that is beautiful, no smaller than 2 inches long (max. size), no bigger than 7 inches long (max. size), easy to keep, peaceful to tank mates,and will eat shrimp. That is why I was thinking about getting a Caucatuoides. They meet most of those criterion. I was also thinking about getting Blue Rams instead of Caucatuoides but someone told me they were difficult to keep alive. Whichever cichlid I get (Caucatuoides or Blue Ram), I would like to keep some non-cichlid fish from whatever region they are from in the same tank because a tank with only two fish is a boring tank. Do you know of any fish web sites that have a search engine that allows you to search according to where the fish come from (native country), fish's max. size, and water conditions?

Answer
Again... sand and gravel will raise and lower pH depending on the carbonate content of the rock... typically play sand or quartz rock should not effect the pH... but you have to be very careful with substrate.  Plants tend to now effect pH either but dead plant leaves, etc will lower pH.  The filter may have too much current depending on how low the intake tube reaches.  Mid-level intake tubes work best for cichlids which are primarily bottom dwellers.  Have you considered Discus??? They are cichlids and very colorful and mostly not aggressive at all. They have more specific water requirements but they are not difficult to keep.... Blue rams would be able to be kept with Discus as would smaller fish such as rummy nose tetra.   I am not too familiar with other fish sites... dave