Cycling and brown algae concerns

[CapnSmee]

I bought a 29 gallon tank about a month ago. There are 2 Java ferns (look so-so now), 4 female bettas, and 2 corydora catfish as well as plastic and silk decorations. The sales associate told me to set up the tank and wait a week to add the fish.
I did what was advised. Since then I had (what I think) a bacteria bloom and online said to hold off on water changes because it would disrupt the process. The water cleared, but 10 days later I now have brown algae and a nitrite spike. In 12 hours I have changed 50% of the water. Went from 5 ppm to 3 ppm.
Should I continue to change 50% over several hours? Is there a way to remove the brown algae stains without causing more harm to the fish? After I get the nitrates and nitrite levels in safe zones, would it be beneficial to add a few cherry shrimp for the algae?
Any tips for a newcomer would be appreciated.

 

[Essjay]

Cycling - any level of ammonia or nitrite when there are fish in the tank is bad for fish. Both must be zero. For a fish-in cycle, the water should be tested daily for ammonia and nitrite and a water change should be done whenever either of them read above zero. The person who told you not to do water changes gave you poor advice I'm afraid. If nitrite is currently 3 ppm you need to do as big a water change as necessary to get it down to zero. This may mean a 90% water change or several 50% water changes back to back.
Ammonia burns the fish's skin and gills which makes it hard for them to take up oxygen. Nitrite binds to the fish's blood and prevents the blood absorbing oxygen.

The brown algae is diatoms which are common in a new tank. It's caused by ammonia and light. It should go away by itself shortly after the tank is finally cycled - that is, when ammonia and nitrite stay ate zero.


Nitrate will not go down to zero; the lowest it can go is the same level as in your tap water. But levels of nitrate above 20 ppm are harmful to fish in the long term so we should aim to keep it below that level. Many places have high nitrate in their tap water which does make this trickier. If your tap nitrate is below 20 ppm, regular weekly water changes (once the cycle is complete) will keep it below that level; if tap nitrate is above 20 ppm, there are ways to lower it.

 

[Essjay]

2 corydora catfish

Once the tank is cycled, I suggest getting more corydoras of the same species. These are shoaling fish which need to be in a group of at least 6 with more being better.

 

[CapnSmee]

Once the tank is cycled, I suggest getting more corydoras of the same species. These are shoaling fish which need to be in a group of at least 6 with more being better.

Thank you for sharing your knowledge. The last 2 days my ammonia, nitrite, and nitrates read zero.
Is there something I should be doing about removing the brown from the various pieces in the tank? Or do I let it run its course? I have scrubbed the plastic plants, glass, silk plants, and shelters. I have been vacuuming the stone as well. But the silk plants look stained all times . I've seen some sites recommend bleach or vinegar, but I've only used water because I'm not completely sure that information is correct.

 

[Essjay]

I would prefer not to use vinegar or bleach on silk plants as washing may not get rid of it all. It's OK on hard surfaces as those don't soak up bleach/vinegar so it's easily washed off.

Diatoms usually go away after the cycle has finished. But every tank is different so it's impossible to say how long.

 

[CapnSmee]

I would prefer not to use vinegar or bleach on silk plants as washing may not get rid of it all. It's OK on hard surfaces as those don't soak up bleach/vinegar so it's easily washed off.

Diatoms usually go away after the cycle has finished. But every tank is different so it's impossible to say how long.

Thank you again.

 

[enricosonic]

A few weeks ago I had the same problem mid-cycle and like Essjay said, the diatoms just went away on their own. All you have to do is wait it out.

 

[CapnSmee]

A few weeks ago I had the same problem mid-cycle and like Essjay said, the diatoms just went away on their own. All you have to do is wait it out.

After they go away, will the silk plants still have like a stained look? Or will all signs of the diatoms go away?

 

[enricosonic]

After they go away, will the silk plants still have like a stained look? Or will all signs of the diatoms go away?

I only have live plants so I can’t definitively speak about silk plants. Once my ammonia and nitrites were consistently reading zero and I did my first big water change, I simply took the siphon tube and gently knocked the leaves of my plants and it loosened the diatoms, which were really just resting atop the plant’s surfaces. Vacuumed them right up and away. Most of the diatoms just disappeared on their own on other surfaces.

Again I don’t have silk plants but I doubt they’d become permanently stained from diatoms. Try gently vacuuming them when the time comes.