CichlidFish.com - Fish That Think.

I am new to cichlids and probably need some guidance. I have only had cichlids for the last few months and not sure about PH and all that so that could be the issue. I have a 55 gallon aquarium with a parrot hybrid that was given to me, 1 kenyi- not sure if I spelled the fish right- 1 yellow lab, 1 frontosa, dolphin fish, and 2 baby tropheus, 1 electric blue and 2 chinese algae eaters. I clean the tank weekly for the most part sometimes every other week. I was out of town last weekend so did not clean the tank until yesterday and took out a bit more water than usual but not even quite half and filled it back up and within 10 minutes my dolphin(Cyrtocara moori) started swimming crazy and would fall the the bottom on his back, within a half hour he was gone. All the fish seemed stressed and this morning I woke up and my electric was dead also. Well the rest of the fish seem ok but my frontosa is not eating, he just seems a little sluggish, still moving rocks with his mouth to make the perfect hole but not rushing up for any food this am so I am afraid he will pass too and he is so pretty. Can anyone please point me in the right direction so that I can go purchase whatever it is that I need today. Is it too late for my front?
I posted about the dolphin on another forum before he died and not even one response so I am trying here.
Thanks

Welcome to the forum.  Sorry to hear about your trouble.  If you can give us a little more information it would help us in giving you an answer.  The first thing that occurs to me is that you have a lot of fish in that 55.  What size are they?

Do you have water test kits?  If so, please let us know readings on:

pH
ammonia
nitrite
nitrate
temperature

What kind of filtration do you have?  When you say you cleaned out the tank, please describe exactly what you do, and how much water you replace, as well as how often you usually do it.  When you do replace water, it should always be within a degree or two of the water already in the tank.  If you aren't using aged water, be sure to use a dechlorinator. 

We'll look for your reply.  Good luck!

well I will try my best but I am not sure of the proper tank "lingo" the biggest fish is the parrot cichlid and she is very large but the rest of the fish are small enough that they could fit in her mouth but she does not bother them and never has. They are all tiny so I figured I had 6 months or so to invest in a larger tank. I do not know the water but I took a sample in today and had it tested and it all tested normal.They told me that it was probably an outside source since the fish died so suddenly but I do not know what that source would be. Temp is around 73-76 degrees.
I clean the tank with no spill tank pump and take out about 20% of the water maybe? I just take the pump and clean the gravel with it and then fill it back up with that pump with water around the same temp. I also used the stuff that conditions the water after each time I clean the tank. I have a filter that has the bio fuse filter things and have two power heads. It all came with the tank so I have not messed with things. I have always had fish for years but easy fish like gouramis and stuff and have never had a problem. I am trying to learn more but it does take time. I feed both the cichlid small sticks and the tiny cichlid pellets for the small fish but the parrot likes the sticks. Does anything I am doing sound wrong?

No, doesn't sound like you're doing anything wrong on the face of it.  You really should get water test kits for the things I mentioned -- ammonia, nitrite, nitrate, and pH.  Having someone tell you they're "normal" just isn't enough information, especially if you're having a problem.  For instance, if you know the exact nitrate reading, it might indicate that you should adjust your water change routine, or the amount you're feeding, or whatever.  BTW, the usual way to express fish size is in inches.  For purposes of this discussion it doesn't have to be exact -- just gives us a relative benchmark knowing the species involved.  The most common error people make is feeding too much.  Put in what they'll eat in about 4 minutes.  Any more than that will just screw up your water. 

On water changes, especially keeping cichlids, I've found 20% a week to be not enough.  This is a subject that will spark some lively debate.  I'd suggest subscribing to one of the fish magazines and synthesizing your own opinion based on the research-based information you'll find there.  It's always better to know why you're doing something (like water changes) than to just follow someone else's advice.  That way you can make adjustments based on your own situations.

Good luck, and keep us posted!