The Planted Tank Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
29 Posts
Discussion Starter · #1 ·
I started a walstad method 40g breeder tank this past friday. I used MCOP and black diamond for my cap. The main question I have is when do you add your fish? I know some add fish right away, but I was warned with MCOP I will have a ammonia swing as the soil decomposes. Should I wait until after the swing...and also is it better to do water changes during that period or to let the tank stable itself?
 

·
Registered
Joined
·
96 Posts
Your substrate should have enough ammonia to start the cycle. Even potting mix has ammonia in it. You have to make sure you have a bit of circulation in the tank so that the bacteria colonies have O2 to survive and multiply. I say keep an eye on your ammonia levels...
 

·
Registered
Joined
·
3,417 Posts
As dougolas said, make sure the ammonia you have, has no surfactants or any other additives. It will likely be a 10% ammonia solution with water.

Test your water to see if your substrate has leached any ammonia - if so, and you have a reading of between 2 and 4 ppms, that should be good to get things started.

Test every couple of days, and should it test out at 1 ppm or less, then add some ammonia - try 2 or 3 teaspoons of the 10% ammonia solution which should be good for your 40 gal to test out @ around 3-4 ppms. Keep adding a couple of tspns of ammonia every time the test shows the ammonia level in the tank has dropped to 1 ppm.

It will very likely take from 4 to 6 weeks to go through the entire cycle, during which nitrites will have peaked and reduced, and your water has developed a reading for nitrates.
When your tank tests 0 for both ammonia & nitrites within 12 hours or so of adding the last batch of ammonia - you'll be good to go. Just do a good-sized water change at that point to reduce the nitrates level.
 

·
Registered
Joined
·
1,090 Posts
I'd like to add another option. If you have a heavily or moderately planted tank, or can buy a lot of fast growers, that's all you have to do. The plants will take care of the ammonia. I did it after my fish food cycle stalled.
 
1 - 10 of 10 Posts
Top