Imo, your pleco is what makes the tank overstocked. They get really big and produce tons of waste. He should be in a 55g.
Here's the profile on the
common pleco.
I'm glad you got him some wafers. I'm pretty sure they can't live on algea alone
Running the filter for a week with out a source of ammonia will not cycle your tank.
Cycling can take a month, give or take a couple of weeks. In order for the bacteria (that sustains your tank) to grow, there needs to be a source of ammonia.
Here's a basic explanation of the
nitrogen cycle:
First your ammonia (from fish waste and left over food) will rise.
In a few weeks bacteria will start to develop and you'll see the
nitrite levels rise and the ammonia levels start to drop.
After a few more weeks a different kind of bacteria begins to develop and you'll see the
nitrate levels rise and the nitrite levels drop.
Ammonia and nitrites are toxic to your fish.
So until your cycle is complete, you need to keep the levels down with 50% daily water changes.
If your
pH differs greatly from tap to tank 2 25% changes a day would be safer.
Using Prime as your water conditioner will detox the ammonia for 24 hrs between water changes.
When you having readings of 0 on both ammonia and nitrites with some nitrates showing, your cycle is done.
Here's a more detailed explanation of the
Nitrogen cycle
If you don't have one already, it would be a good idea to get a liquid
test kit. Try to avoid the strips, they're not accurate and more costly in the long run.
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I am really sorry. I think I had 2 threads up at the same time, and the other was for a 10.
I've done that too!