New tank cycling


Fish Crazy
Feb 14, 2024
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I have a new 40 freshly filled yesterday with well water. It has gravel substrate but no decor yet, that is to arrive next week. After the water raised to 80f I added a small pinch of flakes and maybe a qtr algae wafer. This am I took the carbon filter from the existing 20 gallon tank that has 4 Molly, 5 neon and two mystery snails and inserted behind the filter in the filter box.

I am considering adding a few rosy minnow to speed the cycle. Once cycled the minnow would be transferred to my pond which contains goldfish and Rosie’s.

Is this a good method to cycle.

Tank will eventually contain a couple of angels with perhaps some mollies and a cat.
NO it is not. Unless you know what you are doing, which is very rare for those of us when we first start in the hobby, cyling with fish will result in harm or death to the fish.

Next, flake food is almost useless for making ammonia s it lacks enough organic matter. Using foods will make a nasty mess in the tank and may also facilitate an algae bloom.

This site as a good article with step by step instructions for doing a fishless cycle, it also has two articles on how to deal with a fish-in cycle gone wild. If you use the method in the first article then you will never need the other two.
Thank you for your reply. I will study the link you provided.

I am not entirely new. Had a 55 years ago. We left for a weekend and a winter power outage in our area occurred while we gone. All plumbing and the tank were frozen when we got home.

However I forgot much, although I got the 20 up and running without any major problem a month ago.
Do you have a test kit ?

Your one month old tank is certainly not mature enough to be used to seed another one.

If you have fishes inside. It's more likely to be in the middle of cycling at the moment.
I do have a kit. Last test results on the 20 —
Alk 6
GH 257
PH 7.4
Phos 4.9
Ammo .2
Nitrite 2.0
Nitrate 19

Test date 2/12
In the 20 yes —- 4 Molly, 5 neon and 2 mystery snails right now. None in the new 40.

Had considered the minnows because we had a dozen in the pond along with 5 goldfish. Migrating geese raided the late fall and got all but one of the minnows. All goldfish survived the raid thankfully.
It is in the middle of cycling indeed.

I would suggest to do incremental water changes until nitrite goes close to 0.25 as soon as possible. If these reading are accurate your fishes are in water with a deadly level at the moment, anything above 0.75 is considered stressful.
Thank you ——- I did a 22 percent change on the 12th after the test (4 gallons in what I est is 18 gallon in the tank) and will do another this afternoon with 4 gallons. Will retest in the morning unless I should do sooner.
Continue back to back water changes until you are near 0.25 Nitrite.

Make sure the new water has close matching temperature and is correctly treated with Tap water conditioner.

In the following weeks don't let it go over 0.50 until it recesses on it's own.
We have well which I had tested at the fish store before starting the 20 and told it was ok to use as. I add it at about 80 degrees which close to the tank temp. Thank you for the help.
Hello. There is a means of setting up a tank and enjoying your fish from day one. There is no harm done to the fish either, I can guarantee it. I learned it roughly 20 years ago and the process has worked many times for me. To me, there's not a better way to set up a tank. The procedure isn't difficult, but you can't cut corners.

Good morning. It involves the use of a water treatment and a bacteria starter. There's a specific process, so I'll probably need to explain the instructions in a couple of postings. So, it begins by setting up the tank with all the necessary gear and plants. Once you've set it up, you fill it and add APIs Tap Water Conditioner and Quick Start to establish the bacteria. Just dose according to the instructions on the containers. I have larger tanks. So, to me, the process is much easier. I used two tablespoons of the Quick Start and half a tablespoon of the liquid water conditioner for a 50 gallon tank. But, again, dose per the instructions. You have a small tank, so dose accordingly. If you dose a bit more, that won't hurt anything. Then, just allow the tank to run for a couple of days to establish the water temperature. No fish yet, though. That's enough for now. Just take it easy and proceed slowly.

Rather than use API Quick Start it would be better to use either Dr Tim's One & Only or Tetra Safe Start as these two contain the correct species of nitrite eaters, while the API product does not.

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