I have a 190ltr corner tank with 23 fishes the fish are doing fine i've had them about 6 months, I have stone and some live rocks as I tried to make it a reef tank but the problem I have is keeping corals I have a few mushroom corals and a leather coral every time I try any other corals they just fade away what am I doing wrong, I do a water change every three weeks Ihave 2 power heads, a fluval external filter, a skimmer,a uv filter good lighting
I'M at a loss any ideas bill

Bill, I'm glad that you've been having success with your 23 fish in 190ltr (45-50 gallons US) of water. Actually I'm amazed that you haven't lost them. I have 8 fish in my 800liter (200 gallon) reef.

Without knowing your tank parameters, I'm just guessing but I think that you may be trying to add LPS, SPS or more difficult softies (they won't make it). You probably are also experiencing fluctuation in nitrate and nitrite (due to the fluval). Finally, you may not have sufficient lighting to accommodate more delicate corals.

Not to be a spoil sport but I really believe that you will need to reduce fish load significantly if you want to have a successful reef. You may just want to be thankful for the success you've had and enjoy what you have.

__________________
Doc

Dr Hank's 200 gallon Reef Tank
http://www.aquariumforum.com/f46/drhanks-tank-3440.html

thanks for your advice it looks like I will have to reduce the fish population
thanks again bill

What light do you have? Mushrooms do well at lower light level so check your light will be enough if you lower your fish load.