Tank Cycling Chemistry Question

[HeyMikey]

This newbie's trying his 1st fishless cycling in a 55 gal (http://www.aquariumadvice.com/articles/articles/23/1/Tips-and-tricks-for-your-fastest-fishless-cycle/Page1.html), and already running into problems. Tank has gravel, 250W EBO-Jäger heater (85°F), Marineland HOT 250 gph filter (activated carbon media), and a long air stone at the end of the tank opposite the filter. No lights or lid yet...

I calculated (spare the details unless someone asks to see them) it should take 7.2 mL 10% ammonia to achieve ~5 ppm in 38 gal (interior measurements – ~5 gal gravel) I assayed ammonia and pH (Red Sea Fresh Lab Deluxe—only ammonia kit the local Big Fish Box had) initially and >1 hr after each addition with these results:
Date Addition. . . . . . . . . . pH . Ammonia (ppm)
1/8 . Initial . . . . . . . . . . . 8.0 . . 0.0 (both normal for this area)
1/8 . 7.2mL Ammonia. . . . 8.6 . . 0.0 (pH test max is 8.6)
1/8 . 7.2mL Ammonia. . . . 8.6 . <0.25
1/9 . 50mL Ammonia . . . . 8.6 . . 0.5
1/9 . 160drops "pH Down". 8.6
1/9 . 240mL Ammonia . . . 8.6 . . 1.0
1/10 160drops "pH Down". 8.6 (Now even I can smell the ammonia)
1/11 200drops "pH Down". 8.6

Obviously the test kit is bad (of course!) or I am incompetent (more likely). Somebody on another thread mentioned the Ammonia test is tricky—must admit I'm not sure how you can add the crystals, cap, and shake for (only) 2 sec before adding the drops to shake for 20 sec. Just how precise must those times be? How gently do you shake? (I held the tube ~horizontal and rocked it back and forth 1/sec). What am I doing wrong? Please answer soon—the fish are getting worried I'm going to open their bags (just kidding).

Thanx,
HeyMikey

 

[BigJim]

Don't bother with the pH. Ammonia is very basic and will alter your water chemistry during the fishless cycle. After you're finished cycling and have done a large PWC, test your pH.

Also, dose your tank to 4ppm of ammonia and leave it alone until you see your ammonia levels drop. All that extra ammonia has probably stalled your cycle. Do a large PWC and start fresh.

 

[ejaramillo01]

Ammonia test

I have a liquid API ammonia test. For sure something is wrong with your test kit. The Ammonia test is not that tricky, what you did shaking the tube just up/down should be fine.

Check how old is the liquid bottles, I hear that if are more than 3 years old, they won't give accurate results. In the top of the bottle you can read the lot number, the last four digits are the production month and year.
Do as BigJim suggested and re start again.

 

[HeyMikey]

Thanks so very much for the input. I was starting to think I'd lost my mind…

Well color me embarrassed—I think the QA guy just bought an expired test kit. The "Expiration Date" on the box bottom is "10" which I take to mean "2010"—no wonder it was on sale…

Guess we do a TOTAL water change, assuming my original calculations were correct—does 5.8 mL sound like a good ballpark figure to add for 4 ppm? Here's my thinking:

38 gal (43 gal based on measurements – 5 gal gravel) = 144,000 mL
144,000 mL x 1 ppm = 0.144 mL pure ammonia
0.144 mL pure ammonia ÷ 10% (ammonia label concentration) = 1.44 mL/1 ppm ammonia
1.44 mL/1 ppm x 4 ppm target = 5.8 mL to add

Please let me know if I've got any of this wrong!

Thanks again,
HeyMikey

PS Guess I should have read the cycling article more carefully—I just assumed pH close to neutral would be better for growing the appropriate bugs, but the article doesn't say that at all—live 'n' learn…

 

[BigJim]

Try calibrating your pH kit before you give up on it. Get some distilled water and test it. Good distilled water should have a pH of 7.0.

I missed the ammonia readings above. They seem wrong. 7.2ml of 10% ammonia solution will give you more than 4ppm of ammonia in 40g of water.

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