Ammonia and Nitrite levels question

DaveAngus

Hey guys.
Im brand new on this forum so i want to start by saying Hi and I hope to get to meet everyone here a bit.

I have a 30 gallon aquarium running right now (about 1 year old) and I recently purchased a 75 gallon aquarium. On my 75, I put an old USED filter from my 30 on it to help speed up the nitrogen cycle and also added some lovely bacteria filled water from my 30's water change into the 75 (about half of the 75 is comprised of water from my 30). Now I have been checking my levels and my ammonia and my nitrite levels are great! my pH is slightly high (7.5) and lowering daily. This has been up and running for about 1 week now and I haven't seen any ammonia or nitrite changes yet. I do also have 4 mollies in the tank right now for cycling purposes as well. Now on to my question...do you all feel its safe to start adding other fish or should I hold off? I was thinking about transfering my gouramis from my 30 into the 75 because they are very hardy and did quite well when i started my 30 (and added them only 3 days in to a fresh tank at that).

Please let me know your input.
Thanks,
-DaveAngus

surfnchk

Hi! Let me start out by saying welcome to the forum! I joined a while ago and it has been IMO the best! Everyone on here is very helpful and it's a great source of information.

Sounds like you know the basics of the aquarium hobby already by upgrading to a ncie 75 gallon tank. Since you have added some gravel and used the filter from the 30 that does speed up the nitrogen cycle. Are you adding any supplements to the filter or water? Do you have any live plants in there? (using stress-zyme is great)

Seeing as you already have some fish in the tank with your readings so far it's going good. I would probably hold off on adding more fish in my opinion for another week or so.
A Beginner's Guide to the Freshwater Aquarium Cycle

Hope that helps! See you around the forum!

1077

Four mollies in a 75 gallon tank would prolly not create much in the way of stressful or dangerous levels of ammonia or nitrites and the borrowed bacteria from your thirty gallon tank is helping also.
So long as you perform weekly water changes and do not add more than two or three fish every ten days, I would feel comfortable were it me.
Would NOT add any more than two or three fish every ten days to allow bacteria to catch up with the increased Bio- load on the filter and bacteria contained there for at the moment,,, the bacteria has developed for the waste created by four mollies and the food being offered. To add TOO many fish at once,or too large of fish at once ,will most assuredly result in increase in ammonia and nitrites that may rise to dangerous levels in a matter of a few hours.
Most of the benefits you have received thus far, are due to the borrowed filter from the 30 gallon assuming it was running at the time you removed it and placed it on the 75 gallon. There is very little bacteria in the used water from a cycled tank for the bacteria ,or bio-film as it is sometimes called ,,adheres to solid objects such as decorations,wood,plants, glass,and gravel or substrate.
Would add the fish as described were it me, and feed the fishes sparingly perhaps once a day.

VTonic

Hi and welcom to the forum, just know that there is a vast ammount of information here and a ton of people that love to come on here at 1 in the morning and aswer questions cause they have nothing better to do (ie. me...) Most of you luck with your levels is due to the used filter media that you are using, that being said, good job itll save you a lot of time on the cycle. Now, as far as adding fish is concerned, I would only add 1-3 at a time and wate a little over a week for the bacteria to catch up to the increased load 8-12 days i would think should be fine. If you have live plants in the tank that will help a lot too.

Romad

Was going to post what 1077 already covered. Add a few fish at a time to let your bacteria catch up to the new bio-load.

I added too many fish at once to a very understocked 75 gal. that had been running for 4 months and my ammonia spiked within two days. Not good!!

Byron

Your question has been adequately answered by previous members, so I am just welcoming you to Tropical Fish Keeping forum.

Byron.

DaveAngus

Hey guys.
Thank you all for the input. Thats what I was planning on doing. Adding some hardier fish to have some fun in the 75 gallon aquarium. I put a polypterus retropinnis in today and He's loving it! Very relaxed and loving all of the shelter in the aquarium.
I wasn't planning on putting more then 1 or 2 in at a time.
Thanks a lot for everything guys as it really helped!

Byron

I trust you do know that Polypterus retropinnis attains 14 inches, and will likely eat anything small enough to fit in its mouth--like the mollies mentioned? I suspect it appreciates the cover, since it is a nocturnal species with very poor eyesight. It is also good at escaping, so ensure the tank is securely covered with no openings.

Byron.