Stuck in a Fishless Cycle...

[tastic]

This has been going on for about 6 weeks.

This is my first freshwater tank, it was a Christmas gift and I planned to put it in my son's room by the time he arrived (mid-April). It looks like he may come before the tank is ready at this point.

First the background - It is a 20 gal tank with two medium-sized plants (which are doing very well it seems). Our tap water is very hard, around 8.0 Ph. I have about a 75/25 mix of tap and RO water courtesy of Wal-Mart that stabilizes at around 7.6 - 7.8. Temp is stead at 76 F.

I am using ammonia (10% concentrate) found at the local ACE Hardware. I dispense it from an eyedropper bottle. I'm not sure how the drops translate into ml. I added 15-20 drops to get to 4 ppm, then backed it down to 10 drops as a "maintenance" dose in the morning, and then I would test in the afternoon.

Initially, the cycle seemed fine, my ammonia had dropped to 0, nitrites were high, but I had steady, if gradual, rise in nitirites, topping out around 5 ppm.

I expected to see the nitrites drop off and then I'd be ready, but then the horror struck the last week in February.

First the nitrites flatlined, then, a day or two later, I had a few algae spots on the tank (brown/green, around the size of a dime). I scrubbed them off and then the pH crashed, down to 6.6 in a matter of days.

Ammonia processing seemed to slow down, so I did a massive water change, maybe 60-70% which has restored the pH to around 8.2 or so. Dechlorinated the water before adding it.

As the aqarium needs to be topped off with a gallon of water ever 10-14 days, due to evaporation loss, I plan to do this with RO water. This will step down the pH gradually as time goes on.

Today, the pH is 8.2, I put 10 drops of ammonia in the morning, but by testing 12-14 hours later, ammonia levels are zero. Nitrates are through the roof (80 + ppm). No sign of any nitrates. Also no recurrence of the alage (so far).

My essential questions are:

1. Why the pH crash earlier, did this (or in combination with the alage) kill of the nitrites?

(I suspect this is related to the use of the RO water, which begs the questions: (a) is it even necessary to tamp down the baseline pH of 8.0+; (b) if so, is there a better way to go about it; (c) is there a way to use the RO to tamp down the baseline pH w/o it causing this massive crash?)

2. Any ideas on what I'm doing wrong?

3. Anything else I should be doing?

Thanks in advance.

 

[Nolapete]

Stop doing water changes for a week, add ammonia daily, then test at the end of the week. You seem to be doing too much and most likely your cycle has been done for a while.

 

[feederfish]

Ammonia goes to 0 ppm. Now your nitrite goes to 0 ppm. And your Nitrates get larger! OMG, Sounds like your cycled. I am new to this too, but I am desperately waiting for my nitrites to go below 1.0 ppm. They were maxed, but still not getting to 0 ppm in 24 hrs.

pH crashing sounds bad. Did you use any chemicals to clean algae?

 

[SuBXeRo]

To start off, it is not necessary for you to use R/O water in a fw tank, infact it isnt recommended. The minerals found in the water are fine in the tank. When you buy your stock, most likely from the LFS, the fish have been living in the high ph water of the city for a whileand have begun to acclimate to it. The change in ph is more harmful then keeping it constant.

As for doing the fishless cycle. You are not supposed to do any w/c's until the cycle is complete and you top off the tank with water as needed. IT is crucial that you dose the tank the same amount everyday until everything zeroes out the next day same time before you dose your next amount of ammonia. It is ok to have 20ppm of nitrates at the end. The different types of bacteria that are used in the nitrogen cycle take different amounts of time to grow. Ammo bacteria seems to be the quickest while nitrate bacteria seems to take the longest. Warmer water is also good because it helps to culture the bacteria. It also helps to have a well aerated tank.

It isnt uncommon for aquarists with smaller tnaks to come forward and say they are having cycling issues. Moe often than not, smaller tanks such as 10-20 gal tanks have trouble establishing themselves while larger tanks seem to take to establishing much easier.

I just finished cycling my 72 gallon tank last night after about 4-5 (i havent been keep track) weeks of cycling, that was with a bacteria boost from my 20 gal established tank. Not once have i changed the water, only topped it off as fishless cycling guidelines state. The alge that is forming is most likely from the light on your tank and too much of it for the amount of plants, oxygen, and CO2 mix. Try reducing the amount of time your light is on. 10-12 hours a day should be fine. If the alge persists reduce to 8 hours a day. I also suggest you getting a timer to do this for you so that things become more stable for you tank.

Keep with it, stop all w/c's, top off as needed, make sure that when you dose the ammo you are achieving 4-5ppm after you dose. Each day, maintain that 4-5ppm so that you dont overdose the ammo and kill the bacteria in the tank.

 

[jpappy789]

Topping off with RO will not lower pH or any mineral content. Evaporation leaves the minerals behind.

That being said there is no reason to fiddle with water chemistry. The basic LFS fish will be fine with just about any thing, and pH has zero affect on fish as it is.

You sound like you are cycled, but what type of tests are you using?

 

[tastic]

Thanks for all the quick replies.

I have an API Freshwater test kid (ph, high ph, Ammonia, Nitrate, Nitrite).

I didn't add any chemicals to treat the algae, just scrubbed it off and that seemed to keep them away. I don't put the light on at all since the room it is in has a southern and western exposure. Until the trees fill in, it gets a good amount of sunlight.

I'll add ammonia for the rest of this week, test over the weekend.

Thanks again.

 

[leeser28]

I have a question - you said, "Today, the pH is 8.2, I put 10 drops of ammonia in the morning, but by testing 12-14 hours later, ammonia levels are zero. Nitrates are through the roof (80 + ppm). No sign of any nitrates. Also no recurrence of the alage (so far)."

So do you have 80+ ppm nitrite no nitrate, or 80+ ppm nitrate and no nitrate?

Also, I agree with above, do not use RO water -- my pH runs between about 7.9-8.2 and is fairly hard, and I have never had issues with any of my fish (even with fish coming from the lfs where he keeps the pH closer to 7).

 

[tastic]

Right now, the ammonia is zero within 12 hours of adding 10 drops.

Nitrate is plentiful (40-80 ppm) steadily.

Zero nitrite (which appeared, peaked at 5 ppm, and then and disappeared).

I was under the impression that nitrates had to zero out before I was done.

 

[feederfish]

Nitrites have to zero
Your Nitrates will have to lowered with water change before adding your first fish is the quick newbie answer.

 

[leeser28]

Right now, the ammonia is zero within 12 hours of adding 10 drops.

Nitrate is plentiful (40-80 ppm) steadily.

Zero nitrite (which appeared, peaked at 5 ppm, and then and disappeared).

I was under the impression that nitrates had to zero out before I was done.

Nope - nitrates won't 0. There is not much that will use the nitrate(plants and some bacteria use nitrate but you have to have a very heavily planted tank for the plants to make a difference). Simply said, the nitrate (NO3) form of the nitrogen is not nearly as harmful to fish as ammonia (NH3) or nitrite form (NO2). The main way that we get rid of nitrate is water changes. You're cycled! If you had nitrate level that high you have all of the bacteria you need. Keep feeding the ammonia and just before you add the fish do a water change to get the nitrate level down below 20-40 ppm, and start adding fish.