Fishless Cycle

[maurizio]

1. Is it OK to start changing salinity while starting the cycle of a brand new tank, or will it just make too complicate to follow the cycle evolution? I'm planning to add a few plants at the beginning, and then slowly acclimate them to my final low-end brackish value (SG 1.002), while cycling: 3.5g/l of salts per week, so reaching the wished value in 5 weeks... Can it be done?

2. I read that it's not necessary to do water changes during cycling: sounds reasonable to me, so you don't dilute the present ammonia every time. But is it fully correct?

3. I read that, by the end of the cycle, the tank will be full of algae, due to the final nitrate situation? Sure, before adding the fishes you change the 90% or so, but still... Do I really need to end up with an alage tank, just at the start??

4. Keeping the lights down to a minimum should help in point 3: 6-8h/day?

Thanks!

 

[CezzaXV]

I wouldn't add plants while you're cycling, as they consume ammonia so will give you low readings that aren't due to the bacteria you want.

Water changes aren't usually needed during a cycle, but sometimes they become necessary if the nitrate gets too high or the pH crashes. If a water change does become necessary, make sure you redose the appropriate amount of ammonia afterwards and test your water perameters so you know where you stand.

I'm 30 days into my fishless cycle now and I've not really had any algae, so I wouldn't worry about it. I wouldn't have your lights on at all if you don't add plants until after the cycle, as lights will only encourage algae growth. The ideal cycle would be done in complete darkness (some achieve this by covering the tank), but just don't turn the lights on and you'll be fine.

 

[maurizio]

Thanks!
I was planning to add plants at the beginning, while the water is freshwater, so to acclimate them slowly...

Alternatively, I should cycle first freshwater, then when ready add the plants, and start increasing the salinity. And then finally start adding fishes....

 

[BigbruiserAl]

Dont add any plants during a fishless cycle why? because they need light and with the amount of ammonia in the tank + 6 hours of light it will a tank of green water and slime in 4 weeks

 

[maurizio]

Thanks guys, then I made a big mistake: the plants are coming tomorrow, and I haven't started cycling yet. I thought it was OK to cycle wth the plants in. Well, I'll make a refugium for them (it's sturdy stuff, just Ceratophyllum and Java moss). I hope I can just dump them in a little plastic tank by a window, and do daily water changes.

 

[CezzaXV]

If you have an air pump going spare, might be worth sticking it in your plant bucket to keep the water moving.

 

[maurizio]

OK, a bit of help now: 14 days into cycle, ammonia+ammonium didn't move a bit from the (extrapolated! The chart ends at 3) value of about 5-6 mg/l set at the beginning with ammonium hydroxide (added 9.4 ml for 150 l of water). I haven't bothered measuring the nitrites until now, finally did today, read about 2 mg/l, meaning yes, something is starting. Tap water had read about 0 mg/l in NO2 when I set up the tank.

pH has oscillated a bit since start-up, from 7.4 to 8.

So, why isn't ammonia decreasing,if I'm getting NO2 now??

Should I just ignore the thing, and keep waiting?

 

[BigbruiserAl]

I work out the dose of ammonia at 9.5% soulution at about 6ml sounds like you over dosed off the chart if i read it correctly

 

[maurizio]

Hello,
I'm using ammonia solution 8%. I used the calculator available here in the forum to estimate the correct amount...

 

[BigbruiserAl]

Ah sorry not so bad then you will have prob dosed more anyway using the calc is is does not take, gravel/sand decor

 

[maurizio]

So. Good and bad now: ammonia has finally dropped (measured 0.5 mg/l yesterday), so I added again the amount (8.4 ml of the 8% solution) to reach 5 mg/l.

Today measured all parameters (day 18 of cycle):

NH3+NH4 around or above 5 mg/l
NO2 10 mg/l
NO3 200 mg/l
pH stable at 7.4, but
KH down to 4 dH, compared to first-day measurement of 8 dH
GH 16 dH, compared to first-day measurement of 14 dH.

I understand ammonia will increase acidity, so all my buffer has been eaten up??
Should I consider a water change, given the insane amount of nitrates, or ignore them? Fortuhately no plants in the tank at the moment, so lights are kept off, but they
might arrive by wednesday....

 

[CezzaXV]

I would do a water change to get those nitrates down. As long as you redose ammonia afterwards it'll be fine.

 

[maurizio]

Yeah... Pity I have almost 50 mg/l straight from the tap...

 

[CezzaXV]

Nitrates aren't a massive problem. It'd be better if they were lower than 50 but if that's your tap water then there's not much you can do about that. At 200 it may start to destabilise your pH though so I'd do a water change just to be on the safe side. It's certainly not going to hurt.

 

[maurizio]

Right..
Thanks, will do!