Nitrite problems

Question
QUESTION: Hi, I have a 37 gallon freshwater aquarium with 3 spotted coreys, 2 julii coreys, 3 red wag platys, 1 gold mickey mouse platy who had babies as of 1 month ago.  3 of them survived and are growing. Total of 12 fish.  Temperature is a steady 76 degrees with a heater. I set up this tank on Jan 17.  I test the water almost daily as I had heard about the cycling process and didn't want to lose any fish.  As expected my ammonia went sky high.  During the ammonia spike I did lose 2 fish. I regularly (daily if toxic levels) changed out some water and vacuumed the gravel. Then the ammonia went down to between .025-.1 and my nitrite went to toxic levels.  Sometimes the nitrite is 7-8.  My cycling seems to be stuck right there.  I keep a chart so I can see patterns in my numbers.  The nitrite began climbing on 2/14 and on 2/19 reached 5 and there is where it's been until now.  Other water chemistry: Alkalinity very low sometimes 0, I have a hard time keeping the pH atleast 7; tends to want to be around 6.3; water is on the soft side (50ish).  I have tried everything.  I've tried doing small (5 gallon) water changes; I've tried bigger changes (15 gallon) and I've tried leaving it alone.  I've also had people advise me to use "Stability" and "Prime".  Not helping.  I do add 1/2 tsp of salt for every gallon which may be blocking the nitrite from hurting them.  They don't seem under stress.  Please help me.  This thing of water changes everyday is getting old.  Thank you so much!  --Carol

ANSWER: Hi Carol:  What kind of filter are you using?  Do you have an air stone?  Do you have live plants? How much and how often are you feeding your fish?  For the pH you will probably want to add some coral sand or coral gravel to the tank.  Do you test your tap water?  Can you take a sample of both your tap and aquarium water into an aquarium store and let them test it... just to make sure you are doing this right?  Please let me know.. dave

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QUESTION: My tank is a Marineland Eclipse which came with the BioWheel filtration system.  I have one of those wands that suctions to the back of the tank and produces bubbles up the back.  I do not have any live plants. My tap water is testing fine. I feed them once a day but I feed a variety of things.  Since I have the coreys I feed a couple of sinking pellets, I sprinkle a tiny bit of the powdered baby food for the 3 fry and some Tetra granules for the adult platys.  Once a week I feed them frozen blood worms and sinking pellets only. Please tell me what's wrong and how to help the tank finish cycling.

Thanks for the advice for the ph problem.  I'll get some coral sand.

Thanks for your fast response and your time.  I really appreciate it!!  Carol

ANSWER: Hi Carol:  You have something in your tank that is rotting... its showing up at nitrate for some reason... usually shows up at ammonia which then breaks down into nitrite and nitrate... you need to take all the decorations out and do a really good gravel vacuum... see if there is food built up under the decorations... when you hit those spots with the gravel vacuum... it will be cloudy dirty in the vacuum chamber... I would honestly add about 6 live plants...three on each end... keep me posted... dave

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QUESTION: Okay, then that is what I will do...what type of plants are easy to take care of and good looking?   I also wanted to find out how much coral sand to add to the tank for the low pH. I've seen it before and it seemed like it was meant for high ph tanks (+8).

Answer
Hi Carol: start with about five to ten pounds... and monitor your pH... add more accordingly... Try not to mix the caral sand with your other gravel too much in case you need to take some out...

Plants: I personnally love Anubia, Pennywart, Creeping Jenny, Acorus, and the brazillian swords.... they have been pretty good to me in terms of not needing a lot of care... dave