Alkalinity Question

I have a 15 Gal. Hex tank with 5 mollies and one goldfish. It's been set up and doing fine for about 3 weeks. I usually check the water with Quick Dip strips every 4-5 days and it's been ideal.
Yesterday, the Alkaline Level (KH) showed up between 0-40 ppm!! Is this serious? What do I need to do?
I've had one dead molly in the tank, too!
thanks

 

Just from your description of your tank size and the inhabitants, I'd say your ammonia or nitrite levels are through the roof.  Those test strips are very convenient, but also usually unreliable.  Take your water to your local fish store and have the ammonia, nitrites, and nitrates tested, and tell us what the readings are.  Better yet, if you can afford it, get a master test kit like the one from Aquarium pharmaceuticals and post the results.  The reason I think it's your ammonia or nitrites, is because you've only had your tank set up for 3 weeks, and you have way too many fish in a tank that size, especially one that is not cycled.  I think everyone does this when they first start out, so please don't think I'm criticizing you.  Goldfish are not tropical fish and have different requirements than your mollies.  Goldies are also big poopers and put out a lot of waste.  Most folks recommend 10 to 20 gallons for the first goldfish, and 10 gallons for each one afterwards because of their waste.  Since your tank is only 15 gallons, it's really only big enough for the goldfish in theory.  But that's another topic.  Is there any way you can get another tank that is at least 20 gallons?  You could put the goldfish in the 20 gal., and leave the mollies in the 15 gal.  Also, if you haven't already, please go to the articles here on Fishlore and read up on cycling.  Putting fish in a tank that isn't cycled can be hard on the fish, and you must do daily testing of the water so your ammonia and nitrite levels don't get too high and kill your fish.  Once your tank is cycled, the ammonia and nitrites should stay at zero all the time.  I could go on and on, but let's take this one step at a time.  Please post your ammonia, nitrite, and nitrate levels, and we'll go from there.   

P.S. Welcome to Fishlore!

 

Thanks for the quick reply. The goldfish actually came with the tank. Also 6 neon tetras, 4 zebra danios, 3 black neons and two large ramshorn snails!!! I put all the other fish into my 29 Gal tank and they are doing fine. I left the goldfish in the 15 Gal tank and added the mollies myself.

I'll have the water tested tomorrow (and see how much a good test kit is gonna cost), then I'll post the readings.

thanks again.

 

Oookay,....bought an ammonia test kit and had the water tested at the local pet store. Pet store guy says all levels are really good, including ammonia. I tested the water myself just a little while ago with my new kit. The ammonia level is between 0 and 0.25 ppm/L. Alkalinity (KH) ppm is at 0, ph is 6.8, Nitrite = "safe" and Nitrate is between 160 and 200!!! Yikes. What now?! Will just a waterchange help or do I need to add something? Should I change 25%?

Oh, and I tried to catch the goldfish - No Luck on my part. I uprooted just about every plant in the tank, but he keeps getting away and he's not that small. I'll keep trying.

 

Thanks for posting. Yep. I'd do a 50% water change right away. Then check your nitrates again. Let us know!