Hi everyone! I haven't been having much luck cycling my 37 gallon aquarium and would really appreciate some advice. This may be a bit long (my apologies), so now may be a good time to grab a drink and a bag of chips if you're feeling peckish ;)
Tank: 37 Gallon Eclipse Tall tank
Temp: 78 degrees
Fish: 5 Diamond Tetras
Substrate: Black Gravel
Decorations: 1 Piece of Mopani Wood, 1 Piece of Bogwood, and many plastic plants
I've had the five diamond tetras in my tank for 4 weeks now. I feed them sparingly every other day. Initially, I was doing a 20% water change daily (because I thought I was supposed to do this during the cycling process). I did the 20% water changes daily for about the first 1.5 weeks. A few people suggested that I stop doing this so frequently (because it may not allow the ammonia levels to build up adequately). So now, I'm changing 20% of the water on a weekly basis.
PROBLEM: I have done Ammonia and Nitrite readings every other day, and I do Nitrate readings about once a week. Everytime I've done these readings, I receive a reading of zero on everything. Thinking my test kit may be old, I purchased a new one. Unfortunately, I got the same readings with the new test kit. So, I took a water sample to a local fish store, and they also got zero readings on everything.
My local fish store said with 5 Diamond Tetras in the tank for 4 weeks, "there is no way that you could have had zero ammonia in that tank the entire time." He insisted that my tank has to have cycled, and his explination is that nitrate only registers on the test once it is greater than a certain concentration (I can't remember the number he gave me). He said since I have such a small amount of fish & I've been feeding sparingly, I probably have a very small amount of nitrate that just isn't registering on the test, but it is in there. He went on to tell me that a lot of people expect an ammonia and nitrite spike, but this sometimes doesn't happen in tanks that are very lightly stocked. He said the nitrite level will raise slightly, but I wouldn't have seen a dramatic increase at any point.
So, I went on to ask him if he thinks it is safe for me to add new fish, and he said he would go ahead and add more fish, but slowly and carefully (i.e., continue daily monitoring of the water perameters). I want to add 3 Pearl Gourami (1 male and 2 females) and 5 cory cats. He suggested that I start off with 1 or 2 Gouramis. To be on the safe side, I asked if he had any mature filter media that I could purchase to place in my tank. (I am nervous about adding more fish when I haven't seen the spikes that I expected.) He said they operate on a sump system (I think this is what he said-I have no idea what this is), so they don't have filter floss or a ceramic cartridge or anything. Instead, he gave me some flourite substrate from one of their tanks & suggested that I place it in a stocking in my fish tank. He said this should provide some nitrifying bacteria that should be adequate to support the addition of one or two more fish. I went ahead and added the flourite stocking to my tank this evening.
So, do you agree with what the local fish store is telling me? Is it safe for me to add one or two Pearl Gourami at this point?
If not, what should I do to get my fish tank cycled?
Sorry again that this has been so long. I just wanted to make sure that I gave enough information.
And for anyone interested, I have really learned my lesson about cycling with fish.