Fishless cycling and water changes question

[XimeD]

So, this is my first time fishless cycling. I seeded my 75gal with a filter cartdridge from my 20gal (placed inside the canister filter of the 75gal) and some gravel, set the temp to 84/85F and have dosed with 10% ammonium hydroxide daily to a concentration of 2-3ppm. Only things in there are slate rocks stuck with aquarium safe silicone, a large piece of driftwood (still leaching some tannins but very little) and substrate is playsand. Rocks and drifwood were boiled before they went in the tank.

It's been slightly over a week since I started and I have needed to do 2 >95% WCs so far because my nitrites keep going above 5ppm and I read this can stall the cycle. Last WC was a day ago and yesterday the parameters 2 hours after WC were slighlty>2ppm, 0.5ppm and 5ppm ammonia/nitrites/nitrates respectively. pH is 7.4 and steady (no surprise there since my water is very hard, it'd probably take some conc. HCl to shift that pH)

One day later: 0.5ppm/>5ppm/160ppm. This seems pretty excessive to me, that my nitrites and nitrates are going up so fast. Should I just do pretty much daily 100% WCs to keep those nitrites below 5ppm? Have other ppl run into this?

I'm bummed caused I thought I wouldn't need to do so many WCs for fishless cycling (don't get me wrong I think its the way to go, I will never cycle with fish again because I think it's cruel to the fish unless u really really know what ure doing and I am nowhere near that), but from what I read it doesn't seem like ppl need to do such extreme WCs

I guess the alternative is to reduce ammonia dosing and if some of the nitrosomonas colony dies due to lack of food I would have to grow those again once the nitrobacter catch up. Also can very high nitrates stall the cycle? I haven't come across anything like that in my reading yet.
Thanks for any advice

 

[bluerose]

Test strips or a reagent kit?

 

[XimeD]

Test strips or a reagent kit?

API freshwater master test kit, and I use it at the same time for my 20gal with normal readings, so I am pretty sure its not a bad kit problem.

 

[mattrox]

160 ppm of nitrate seems excessively high for what you are doing.

Take your tank water in to an LFS for testing to confirm your readings. 160 ppm of nitrates is produced from 44ppm of ammonia. You haven't put that much in. Either your test is faulty or there is another source of ammonia in your tank.

 

[XimeD]

Even accounting for the fact that 1 ppm of ammonia forms 2.7 ppm of nitrite then 3.6 ppm of nitrate and the fact that nitrites give a false positive in the nitrate test how can nitrates be so high in 24hrs?????

 

[XimeD]

160 ppm of nitrate seems excessively high for what you are doing.

Take your tank water in to an LFS for testing to confirm your readings. 160 ppm of nitrates is produced from 44ppm of ammonia. You haven't put that much in. Either your test is faulty or there is another source of ammonia in your tank.

Exactly! No nitrates in my tap water either. My LFS uses test strips for testing do you think these are going to be more reliable? Also I ordered a replacement nitrate kit which should be coming in a few days. I can try dosing little/no ammonia and see what happens. I definetly see your point, the mass has to be coming from somewhere, I just don't know where =(

 

[BigJim]

Did you do the nitrate test correctly? The nitrate test is the most demanding in the API kit. There's a chemical that will precipitate out in one of the nitrate test solutions. That's why you have to shake the bottle before adding it to the tube and shake the tube after.

 

[carpus]

Agree, and more...

Something is up with the NO3- test, for sure.

Maybe you should just let things settle in for a while, no more ammonium hydroxide for a while.

Plus, my recent experience with cycling a large-ish tank suggests that big tanks are significantly harder to do than small tanks.
My small tanks responded quickly to donated filter media or some substrate from an existing tank, making NO3- quickly and creating hospitable environments in days. OTOH, my large tank took two weeks to be hospitable to fish, and that was with lots of donated filter media in extra capacity filters, and lots of added biological filter organisms. Perhaps you need more organisms in the tank.

My recent test of bio-additives showed that between Tetra Safestart, Seachem Stability, and Microbe-Lift Special Blend, only Tetra Safestart made nitrates from ammonia. Stability made a bit of NO2-, the other nothing at all.

Did you do the nitrate test correctly? The nitrate test is the most demanding in the API kit. There's a chemical that will precipitate out in one of the nitrate test solutions. That's why you have to shake the bottle before adding it to the tube and shake the tube after.

 

[taylorodw]

I think you should just chillax on it a little bit. Nitrites CAN stall the cycle but don't always.

For what it's worth my tank needed a 90% PWC, followed by a 50% PWC to get ready for fish when I completed my cycle. My nitrates were sky high and for a couple days my nitrites were too, but my tank was quickly able to deal with them.

My suggestion would be to let the nitrites go off-the-chart and if they stay there for a week, you'd know they were stalling your cycle.

The other suggestions will get you through the cycle, they just would be more work

Edit: You can also re-seed or run your 75gal filter if it will fit on the 20gal without blowing everything around too much. Gravel (or sand that is near the top) will also introduce a lot of bacteria.

 

[XimeD]

Got my new nitrate kit (same API liquid only a newer bottle) and was getting the same result. So, I did a 95% PWC and got 0.25/0.25/5ppm ammonia/nitrite/nitrate. I added no ammonia (ammonium hydroxide I should say) and the following day readings were the same wtf??????

That was yesterday, so I added some NH4OH and left it at that. Haven't done measurements today yet, will post when I do.

Chillaxing sounds good =) It's not like there is anything in there to kill (except bacteria, but not counting those) and my other fish are perfecly happy in the 20gal for now (readings are 0/0/0ppm consistently for that one, same kit by the way) so I got time.

Thanks everyone for the advice, keep it coming =) Always willing to learn.

 

[taylorodw]

Exactly, a fishless cycle is going to take a little while and be a process anyway. No reason to work twice as hard to finish 5-7 days earlier IMO.

I edited my earlier post to include a couple thoughts on further seeding your tank, BTW.

 

[XimeD]

Update

So, yesterday my levels were 0/0.5/10ppm (ammonia/nitrite/nitrate). That to me is good news! No crazy nitrate spikes. I did a 50% PWC because my plants finally got here and it was easier to plant the tank if only half full. Then dosed with NH4OH, here's what it looks like:

 

[XimeD]

I found what the problem was

Finally!!!!! I found what my "nitrate" problem was. Should have suspected sooner because there is a thread on this, in short it was the API color cards. Once I got my individual nitrite/nitrate kits got here I compared the individual color charts that came with these kits, with the large one that comes with API master test kit and there is a HUGE difference for colors other than 0 (which is why it wasn't a problem for my 20gal). I will post a pic when I can.

This explains it! I am glad I stopped doing those huge water changes.

Edit: After the dosing yesterday, the levels today came out as 0.5/1/~15ppm (ammonia/nitrite/nitrate) this was with the new cards. Old cards it would have been 0.5/>5/40 (I swear, difference is that big!)

 

[Mark Hewitt]

Usually best to compare against a control sample (i.e. tap water) rather than use the cards IME.

Your sand looks great, but perhaps a little deep in parts, I believe if you have it too deep then hydrogen sulphide can build up and if released would be very bad news indeed.

 

[XimeD]

Usually best to compare against a control sample (i.e. tap water) rather than use the cards IME.

Your sand looks great, but perhaps a little deep in parts, I believe if you have it too deep then hydrogen sulphide can build up and if released would be very bad news indeed.

My tap water has some ammonia, but I guess I could use some DI water.

Regarding the sand, I am planning on keeping MTS in there, they should keep the sand stirred right?, deepest part is 5in (one corner).

 

[Mark Hewitt]

My tap water has some ammonia, but I guess I could use some DI water.

Ah, that's bad news then, how much are we talking about?

Regarding the sand, I am planning on keeping MTS in there, they should keep the sand stirred right?, deepest part is 5in (one corner).

yep! Good plan!

 

[XimeD]

Ah, that's bad news then, how much are we talking about?

0.5ppm, so not that bad.

 

[taylorodw]

If you use prime it will take care of that easily.

 

[XimeD]

If you use prime it will take care of that easily.

Yeah, I do use prime I should look this up but does chloramine test positive for ammonia on the API liquid test kit? cause if it does, I might have that. Regardless prime takes care of that too.

 

[mattrox]

If you have chloramines in water, the dechlorinator will break it up and form ammonia anyway, which a mature filter should quickly take care of.

Excuse the use of "of" at the end of a sentence.