Beneficial bacteria question

[ChrisT]

Hi, total newbie to aquariums. I recently set up my aquarium 150 litre, and let it cycle for a month - no fish just a few live plants. Added some bacteria booster once a day. I recently had to remove all the plants and add new ones, and I really wanted to do this with the least water possible, so I emptied about 80% of the water, and then filled it back up after 2 days. Therefore aquarium was 2 days with only 20% water, but pump and filter still running.

Did I loose all the beneficial bacteria that may have been generated? Is the cycle going to start from the beginning? Sorry but I do not have means to test water as my test strips turned out to be cheap ones and weren't testing correctly. Thanks!

 

[Aiken Drum]

Did you add any ammonia source to your fishless cycle?

The bacteria needs ammonia for food to grow, simply setting up a tank and letting it run for a few weeks wont grow much bacteria.

A large water change shouldn't affect your bacteria (assuming you have any). It doesnt live in the water (or very little does), it lives on surfaces, like your filter media, substrate, inside of the glass, tank decorations.

If you cant test the water you have no way of knowing if you are cycled. API master test kit is considered a good kit to get. It will be accurate enough to cycle a tank.

 

[ChrisT]

Thanks Aiken!

No I am not adding ammonia but some plants died and though maybe the detritus and decaying plants was a source of ammonia? Plus I added biological starter liquid everyday as per instructions on the bottle....

 

[Aiken Drum]

The information given in the post below yours is also relevant to you.

https://www.aquariumadvice.com/forums/showthread.php?t=375923

Adding bacteria without an ammonia source wont cycle your tank. Either do a fish in cycle or a fishless cycle.

 

[fishwonder]

Here is some great information to help you cycle your filter/tank for your new aquarium. Remember it will take 3-8 weeks to cycle your filter for the aquarium.

 

[ChrisT]

Thanks again Aiken! Will probably turn this into a fish in cycle, and yes a proper test kit was always on the cards. Any hardy fish you might recommend which would be suitable for a community tank once cycled?

 

[Aiken Drum]

Dont add fish that you arent intending keeping in your community.

Zebra danios are the go to fish for a fish in cycle. Minnows, platys, and barbs are commonly used as well. Goldfish work well but get big, so not really suitable for a community tank.

Light stocking (1 to 2 inches fish per 10g), feed lightly, test everyday. You should do water changes to keep your ammonia + nitrite combined below 0.5ppm. If it gets to 0.5ppm do 25% water change, if it gets to 1ppm combined do 50% or 2 x 30% a few hours apart. If you are consistently seeing 0ppm ammonia and nitrite, your nitrate should be rising slowly and you are cycled for your current stock and can safely add a few more fish (increase bioload by say 30%). Repeat the testing and water changes as previously and again if you are consistently seeing no ammonia or nitrite add more bioload. Rinse and repeat until you are stocked. You then do water changes to control nitrate, typically to keep it below 40ppm. If you get to the stage where a 50% weekly water change doesn't keep you below 40ppm nitrate you are overstocked. Remove fish or get a bigger tank.

 

[ChrisT]

Got it, Thanks again Aiken!