when to add additional fish

  1. seasmoke1 Initiate Member

    Made it through the fishless N cycle and added three half grown guppy females plus one guest tiny female baby..watching the parameters daily and did a water change..10% also cleaned the very dirty tank. Three questions.. the tank had a brownish algae type substance on the glass...is it algae? At what point may I introduce more fish friends? The parameters are normal Also the filter is the original filter from 4 weeks ago...when should that be changed?
     
  2. STLBluesFan Member Member

    i do believe the brown stuff on the glass is algae.. its usually from outside light. and you should introduce fish slowly.. as to not over load the filter. and with the filter, im not sure what kind of filter you have, if you have one where you have a blue pad with a plastic back and some carbon inside, then that should be changed only when you notice it being clogged up. i myself have filters like that, and i just bought a filter bag made by whisper and with that you can unclip it and empty the filter and just rinse off the pad
     

  3. Wendy Lubianetsky Well Known Member Member

    Rinse the pad off only in water that has been siphoned from the tank do not use tap water on it. Also brownish algae is kind of a new tank syndrome. It seems that for whatever technical reasons it is very common that a tank that has just newly cycled gets brown algae. It will eventually go away. I also think you should be doing more than a 10% water change when you change your water. It should be more like 25%. I know that 25% is a minimum when I change water. Keep your water very clean to help the algae from spreading too much.
     
  4. pitbull_nc Member Member

    Yeah I have always been told to only add fish every 2-3 months so not to overload the tanks bioload. It can take a little bit for the tank to get used to new loads. I don't know if anyone else has heard this rule of thumb but its what I've been told. If you just watch your water parameters your tank well let you know when it is safe to add more.
     

  5. cameronpalte Member Member

    What size is your tank? That may affect the amount of time you can add them. Your filter is 4 weeks old, so if you plan on adding new fish, change the filter to help with the biload.
     
  6. Shine Well Known Member Member

    You don't want to "change the filter" (sorry cameron). The filter media is where most of the bacteria grows that sustains the cycle. If you throw it out, then you risk going through the cycle again.

    I agree with the above posters. Rinse the filter media in used tank water, and return it to the filter. The brown algae will likely go away on its own eventually, but you can scrape it off. As for new fish... depends on the tank size but I'd start with one or 2, then wait a couple weeks minimum to make sure the bacteria colony keeps up
     
  7. jdhef Moderator Moderator Member

    The brown algae is called diatoms. They are very common in newly cycled tanks, and while unsightly, they are harmless. They will go away on their own eventually, but it supposedlly can take up to a year (althogh for me it only took a few weeks)
     

  8. ryanr Moderator Moderator Member

    +1 on the above.

    Most likely diatoms - they will disappear on their own, and quicker with regular water changes. (once a week)

    When to add fish is a bit of a game plan, and the timing is dictated by your tank.

    My approach to stocking a tank is to pick the species I wish to keep, and then put them in order of least aggressive/territorial to most. Add them from least to most.

    As to the timing of when to add, and how many, well depending on what I'm adding, determines how many I add.

    If what you're adding has a high waste output (larger fish/catfish etc), then maybe only 2/3, if however they are low bio-load (many tetra species/shrimp), you could add more at once.

    When you add fish, monitor your parameters regularly, to ensure your filtration (beneficial bacteria colony) is keeping up with the bio-load, and don't add more fish until the parameters are stable again. e.g. If you get an ammonia spike, wait at least a week AFTER the spike has zeroed out before adding more.

    And a word of advice on filter media - NEVER throw away your media - the exception to this is carbon/chemical media and polishing pads (filter floss) [https://www.fishlore.com/fishforum/filters-filtration/74651-3-stages-filtration-what-they-do.html]

    Ken (aquarist48) has been using the same media for many many years.
     
  9. seasmoke1 Initiate Member

    thankyou,.. aqueon filter is the filter it is blocking the water flow because it is so dirty ...it has a months worth of fish food, algae and live plant matter and my additional vacumn job that really stirred up a mess , it is dark green on both sides...it does not seem to rinse off at all ...should I still put that back in?
     
  10. seasmoke1 Initiate Member

    Someone asked the tank size..it is 29 gallon the aqueon filters are replcement type filters white with charcoal inside
     

  11. bowcrazy Well Known Member Member

    First off if I haven’t welcomed you to FishLore let me take the time to do it now. FishLore is a great source for information on every aspect of fish-keeping. From time to time you will see that some of us have a difference in opinion on how to handle things but that is mostly due to our own personal experiences but most of the time we all agree on the basics.

    You have been advised well to only clean your filter media using tank water. I personally siphon a gallon or so of water out of a tank into a bucket so that I can slosh the media around in it. I never change the media until it is absolutely falling apart. The filter is where all the beneficial bacteria lives and the less you mess with it the better off you are. This is not to say you don’t need to clean it because you do, just don’t over clean and cause the tank to have to go into a mini cycle.

    In my opinion you should add more fish very slowly over a several month span. Adding too many fish all at once can cause the tank to loose it’s cycle and become toxic to all the fish. I only add a couple of fish every few weeks so that the tank has time to adjust to the new additions before adding in more. Also I would recommend using a quarantine tank for the new fish so that you don’t introduce any sick fish to your healthy ones.

    Here is a good way of adding new fish. When you purchase new fish put them into a quarantine tank for at least two weeks so that you can observe them for any problems. Once you have decided they are not sick with anything then you can move them to your main tank. This frees up the quarantine tank for more new fish. Once you have your main tank stocked the way you want it you can use the quarantine tank as a breeder tank, hospital tank or a fry tank.