Cycle Problems

[Bill]

A nickel to whoever can help me...

 

About five weeks ago I started adding 10% ammonium hydroxide (from Ace Hardware) to my 100 gal tank to begin a fishless cycle. About 3 weeks later the ammonia levels would drop down to .5ppm in a day after adding it to ~4ppm and the nitrite levels got VERY high, to the point where the API test tube would turn blue-grey, which I later found out indicated a very high nitrite level. I then read that a very high nitrite level could stall the cycling process. At this point my Nitrate levels were relatively low--in the 5ppm range. I read that a large water change might help put the cycle back on track so I did a near complete (>95%) water change. My nitrite still measured very high (in the 5+ ppm range) so I did another very large water change the next day. I siphoned the water until the nitrite reading was zero. The nitrite and nitrate reading were also zero. I then added ~2ppm of ammonia and it took about a week for the ammonia to go from 2ppm to ~.5ppm, but the nitrite levels began reading 2-4ppm at about day 3 or so. Then the nitrates started reading between 0-5ppm. About 4 days ago I added ammonia to ~ 4ppm and it is still at that level currently. The nitrite level is off the chart (5+), my nitrates are SLOWLY increasing and are currently at 5ppm, but my ammonia doesn't seem to be lowering (still at ~4ppm).

I keep the pH between 6.8-7.6 (mostly ~7.3). The temperature is between 88-94F. The system is a constant flood and drain with a 50 gallon grow bed filled with hydroton (similar to Murray Hallam's, but smaller). I am pretty sure I killed off most of my bacteria with the water changes I did-- I did not use purified water, as buying 100 gallons of purified water would not only be costly but impractical to lug around. So my question is: if nitrite and nitrate levels began rising less than 3 days after my water change, then why does it seem as if my ammonia level is falling disproportionately slower? I've heard that the rise in nitrites and nitrates when compared to the fall in ammonia may not be exactly proportional, but can someone explain to me if this is normal and how long it will probably take from here on out (IT'S BEEN OVER 5 WEEKS ALREADY!!). Also, seeing how my nitrites are very  high again, it seems as though I am back at square-one and the water change that slowed me down was all-for-nothing. Once and for all can I get a straight answer: does having a high nitrite level REALLY stall a cycle?? I dont think I'm going to do another water change and risk this whole ordeal again so I'm hoping the answer is no.  

[Anton hahna]

So you would like to know when you can ad fish???? or are there fish in the dank?

[Bill]

Didn't add fish yet.

Anton hahna said:

So you would like to know when you can ad fish???? or are there fish in the dank?

[TCLynx]

Are you dosing with ammonia daily?  or just that one dose?

 

If you are dosing with ammonia daily, STOP, wait till the nitrite drops, having too high an ammonia level can inhibit the bacteria that convert the nitrite to nitrate.

 

I've cycled several systems and I usually don't dose the Ammonia that high and if the nitrite gets too high, I stop dosing the ammonia until I see the nitrite dropping.  Once the initial nitrite spike has passed, you then dose the ammonia and then measure the ammonia and nitrite 24 hours later, once you get to the point that you can dose ammonia one day and have both ammonia and nitrite get to 0 24 hours later, you are fishlessly cycled.  At that point you can keep up with small doses of ammonia to keep the bacteria going until a day or two before you will bring home fish (you want to make sure both ammonia and nitrite are down before you bring your new fish home.)

[Anton hahna]

When I started aquaponics a year ago I used 1/2 rain water and 1/2 water from a nearby fish pond I think that was the best thing I did.   I never added any chemicals my tank is large 8'diameter and 4' deep I probably need to add more Tilapia  I have about 50 now .I live in Florida so in the summer when I started we have lots of rain. I filled the tank, added goldfish because I they were cheaper.   I changed to tilapia I think we have to learn how the fish behave then we don't really need meters????( my thought ) In the beginning I added all my fruit trees  so I would have a large amound of roots for filters to get the good N I can not pronouce different so I call it the good N and the bad N.   The only thing what I do is regular spray with E.M.   I learned everything I know from this blog.  I know you live in Brooklyn but if you can start with a couple buckets of water from an existing fish pond, you will be ahead of the game.

Bill said:

Didn't add fish yet.

Anton hahna said:

So you would like to know when you can ad fish???? or are there fish in the dank?

[Bill]

Thanks for the quick responses! I am not dosing with ammonia daily--I just wait for it to go down to .5ppm or so before I spike it back up. I'll just spike it back up to 1 or 2 ppm from here on out. Can I add my plants to the grow bed with ammonia levels of 4-5ppm and rising nitrate levels? Will this concentration burn the roots or is it OK? Also, if I do add the plants will that slow down the cycling process and/or affect the readings? Thanks again!  

[TCLynx]

I would wait till the ammonia is down a bit more before adding plants, just because traumatized roots might be slowed down a little by ammonia levels above 4 ppm.  But the truth is you can add plants anytime.

 

I expect your major water change set you back (tell us, is your water chlorinated? if so and if you did a water change and didn't neutralize the chlorine or chloramine that is probably what has stalled you out and it may take a few extra weeks to catch back up since the chlorine or chloramine probably killed off much of your bacteria when you did that nearly complete water change.  If you are dealing with treated city water, you need to keep your top ups or water changes very small unless you are doing something to neutralize those things before you put them in your system.)

 

Once your ammonia drops again, keep the ammonia doses smaller and If your nitrite goes off the chart again, don't dose the ammonia until the nitrite starts dropping.  Then after nitrite drops you can finish out the cycling  with the dose then test 24 hours later routine.

[Eric Warwick]

What did you use to keep your pH in check?

[TCLynx]

who are you asking  Eric?

[Eric Warwick]

Bill, he might be adding citric acid to counteract the water being basic due to the hydroxide ion. 

TCLynx said:

who are you asking  Eric?

[TCLynx]

Ah, yea avoid the Citric acid

[Eric Warwick]

TCLynx said:

Ah, yea avoid the Citric acid

[Bill]

I've been using phosphoric acid to lower the pH and potassium hydroxide and calcium carbonate to raise the pH. Do you think the phosphates from the acid may become a problem for the fish or is that not much of a concern? I've been adding about 1-2 ml/day over the course of the week because the pH was buffered from the CaCO3, but I think the pH finally leveled off (somewhere around 7.0-7.2). Thanks!