Started my Fishless cycle

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Fish Fanatic
Aug 19, 2023
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South West Scotland
I have set up a new Aquarium after years of not keeping fish. I bought a Fluval 200ltr tank and started to do a fishless cycle on 2nd August. I have silica sand substrate only added to my tank, I am using the Fluval internal filter supplied with the tank.
At first I started to build up my Ammonia reading with just adding flake fish food each day, and I used Seacheme Prime and Stability, but after 10 days I was not getting any readings at all when I tested my water. I then bought Dr Timms Ammonia and within a few hours my Ammonia reading climbed to 40ppm. I also started to add Fritz Zyeme7 and dozed 4ozs per 10 gallons as instructed. Thats where I am today I test every second day but my Ammonia is still at 40ppm and my Nitrite is 0. When can I expect to see the Ammonia start dropping and Nitrite start to rise. Can I do anything more to help the cycle. I also at the beginning of my cycle added the gloop from my daughters goldfish filter sponge. I thought seeding the tank would speed the process on a bit, but it still has not moved forward very fast
can suggestions to what I should expect to happen next.
40ppm is waaayyyy to high.. you need to be around 3 to 4 ppm or the cycle will stall.

Do a big water change to dilute and start again with Dr. Tims. Follow the directions closely

Get some fast growing plants they will help the cycle
Are you sure the 40ppm Ammonia reading was correct. It wasn't 4ppm ?

I would either do a Dr Tim's or plants but not both. I was out the hobby for 10 years and been back 1 month. I would do Dr Tims and stick to it religiously. He also has good videos.

But yeh, start again at 40ppm. I'd empty the entire tank, clean the filter media and start over with Dr Tim's. No need to use food or stability, or anything except dechlorinator at beginning and water changes (if needed), Dr Tim's ammonia solution and Dr tims nitryfying bacteria. That's what I did, and worked like a treat. Was fully cycled in about 10 days.

I did add some Live plants but it complicated my readings. The best advice seems to be to do one or the other (fishless cycle no plants or plant cycle). I think i read some plants don't like ammonia over 2ppm and some definitely not over 4ppm?

Others who know more can correct me, but at 40ppm ammonia, all the ammonia consuming bacteria would have been obliterated anyway?
Just wondering how much longer will I wait to see ammonia start to drop and Nitrite start to rise. Maybe I am impatient is there anything else I can do to steed up the process I can’t get filter media from another tank to seed mine, but I can get contents of filter sponge that’s been squeezed out. Will this do the same job.
is it okay to leave my carbon filters in the filter while tank is cycling
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It took almost 4 weeks for ammonia to drop and nitrite show up when I did a fishless cycle. Seachem Stability may or may not help as it contains the wrong species of bacteria. Seachem says the bacteria exists in the bottle in spore form but the bacteria we want to grow do not form spores. if you want to use a bottled bacteria, Tetra Safe Start contains the correct species.

I would take the carbon out. Not because it's bad for cycling, but because you don't need it on a routine basis. It's main use is to remove medication after treating sick fish. Either leave that space empty in case your fish ever do get sick, or fill it with more sponge or biomax.
Apparently it's Dr Tims bacteria or Tetra Safe Start or nothing as far as I know.
Sorry, I missed the bit about Fritz Zyme :blush: Many people swear by that, but according to our fishless cycling expert it cannot contain the correct bacteria species as the use of them is copyrighted and only Dr Tim and Tetra hold the copyright.
Different strains of bacteria can handle different levels of ammonia. The first ones discovered were mostly good in such environments, It was believed they were also the ones in aquariums. Dr, Timothy Hovanec in conceret with other scientists pioneered the research which identicied the bacteria that end up being in our tanks, And since then more information has been discovered,

Basically, Dr. Tim and a few associates and Marineland (and now Tetra) share the patent on the Nitrospira bacteria which were identified as the ones which convert nitrite to nitrate. Some years later in a basement tank at a research facility it was discovered these bacteria are also able to process ammonia straight to nitrate as well.

Another discovery was made on the underside of a rock at Public Aquarium. Another type of microorganism, Archaea, had a aquatic strain able to convert ammonia to nitrite. These Archaea are able to thrive on even lower levels of ammonia than the bacteria in our tanks. So it is possible there are none of the Archaea are involved, both bacteria and Archaea are involve or only Archaea are involved. Which we may have seems to depend on the geographic location for aquarium.source of the water supplying it.

It doesn't matter which of the 3 situations described is the case in any given tank, the result is still no ammonia or nitrite once the cycle is established.
So what does this all mean with my tank or any other tank that has not used Dr Tim’s or Tetra products to add bacteria into our tanks. Will my tank NOT cycle or will it cycle eventually
what is the two products called. I have looked and not clear which one I need. What size of bottle will I need to cycle a 200ltr /55 gallon tank.
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The bacteria we want to grow are in our tap water, but in tiny amounts. A tank will cycle without a bacterial starter, it just takes longer.

The most easily available product in the UK is Tetra Safe Start.
There are three different sized bottles, the website says the 250 ml bottle is for a 300 litre tank, so the 50 and 100 ml bottles probably won't be enough for 200 litres.
Sorry I am a bit confused here. Will my tank cycle if I just leave it alone or will it never cycle. If it will cycle left alone, how lone can I expect to wait. My Ammonia reading is still 4ppm. Nitrite 0.
WILL it help if I add the gunk from my daughters sponge filter, this is all I have to seed the tank. I have tried local pet shops and don’t know anyone else that can give me actual used filter media.
This is getting quite com
Yes it will cycle if you leave it alone.

I did a cycle without adding anything except ammonia. It took 28 days for ammonia to drop and nitrite to show up. And it was finally complete on day 48.

Adding gunk from a filter won't do much. The bacteria we want to grow live in the biofilm which is tightly bound to surfaces. If your daughter has a fish tank, using some of her media will kick start the cycle. You can take a quarter of her media - and buy some new media in return. Put her media in your filter, preferably first in the direction of water flow so that any biofilm which does come loose it washing into the rest of the media.
Can you tell us what media your daughter has in her filter so we can suggest the best media to use?

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