Hi John, It is a heavily planted tank with a pH of abt 6.5 and a kH of 2-3 degrees. There's no problem with the swordtails, as I think they've been conditioned gradually (started with a pH of 7.0) and they're trhiving and reproducing ( I started with a pair and have since reproduced many, some are given away while others become live food). I love the cardinals too, but am thinking of giving the swordtails away, as algae is beginning to creep into my tank eversince I added those Kribs and Rams, they just eats alot and excrete alot too. Cheers, Kenny ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!