Please Clear Up Mixed Information!

[khaydn]

Hello,

I have been reading everything, talking with fish store people and frankly now I am a bit confused. I read early on that a new tank (with fish) should be monitored by left alone for the most part. Then every 2 weeks, do a 25% water change, stir up the gravel (to release the good bacteria).

One pet store owner told me I could add fish right away and add every 2 weeks. Another said I should not add any more fish for at least 6-8 weeks.

I am now thoroughly confused but as of yesterday... my 20 gallon tank was right on the money in levels and I had:

1 platy (another platy died within 3 days of purchase)
1 molly in it.

the test yesterday was
Ph 7.6
ammonia 0
nitrite 0
nitrate 5

so I added 3 platys

Now if the levels go wonky.. here I have read change change change your water and clean your gravel. The fish store owner said absolutely not that kills the good bacteria and will make things worse.

So I need to know the REAL answer please. Or am I going to have to just use my gut and wing it?

Thanks!
K

 

[glolite]

The tank water does not contain much good bacteria, this is, for the most part, in the filter media and a little in the gravel and decor. However, there's also fish waste in the gravel which will turn to ammonia and eventually nitrite.

Basically you need to keep ammonia and nitrites as near to zero as possible by doing as many water changes as necessary. And no, water changes will not affect the good bacteria.

Read the fish-in cycling pinned thread in the New To the Forum section for in depth explanations.

 

[OldMan47]

There are instructions for a fish-in cycle posted at the beginners resource center at the top of this forum section or you can reach it by following the link n my signature area. The simple way to look at a fish-in cycle is that you must test often enough to know what your water is doing and you must change water often enough, and enough of it, that the ammonia and nitrites never exceed 0.25 ppm (0.25 mg/l) before the water change. If that means huge water changes, then it does. I got myself in trouble a few weeks ago by trusting a filter to become cycled by running it with another filter in an occupied tank. When I brought home some new fish, I tried to use that filter for them and soon found that it was not really ready yet. For the first 4 days that I had those new fish I changed water by draining the tank until there was only less than 1/2 inch of water left in the bottom of their tank and refilling with dechlorinated water. Each day when I did this, the fish saw a huge, how else to describe it, water change but after the change they looked much better than before the change. During those 4 days I was finding nitrites at 0.5 ppm each day before the water change. The filter finally caught up with the biological load on day 5 and I returned to weekly changes on that tank.
The real point to this is that the filter that was essentially almost cycled went to fully cycled while I was changing so much water that I could not estimate how much more than 80% it was. The water going out of the tank did nothing to slow the cycle but it sure made the water safer for the fish. The only consideration when cycling with fish in the tank is keeping the tank safe for the fish. The cycle will happen no matter what you do to keep the tank safe.