Fishless Cycle Question

[coldcazzie]

Setting up my QT which is about 7.5 US gal/28.8 litres.

My stocking plans for my Rio 240 are:
- 2 angelfish (currently have)
- between 8 and 12 corydoras, depending on type
- about 15 buenos aires tetras
- possibly a rainbow shark, but not convinced about that (is only a maybe, if not might increase the number of tetras, or maybe add some otos into the mix)

Keeping that in mind, I'll only be having about 5 fish in my QT at any one time, so how much do I need to dose the ammonia to during the fishless cycle? I can't see the filter needing to deal with as much as 4ppm, so would dosing to 1 or 2ppm be alright?

Never done a fishless cycle before...!

 

[waterdrop]

There's a little bit of a "quantity" aspect to matching the ammonia concentration built colonies to the eventual actual fish bioload that you describe, but not as much as you might think. I'd still maybe aim for 4ppm or possibly (only possibly) 3ppm as a final number at the end of the fishless cycle. The thing is, you want to get the two species of bacteria as "robust" in their new colonies as possible. You always have to have them be "too big" for the bioload and then have them drop down to match it, because the other way 'round doesn't work. It doesn't work to have have the colonies too small or to exactly match (well, it might but you'd never hit it in practice.)

Unfortunately, as newcomers to the hobby we all get stuck with this situation of wanting/needing to get both the display tank and the Q/H tank up and going and usually not having any mature media from ourselves or any nearby fellow hobbyists. Its just a big slow painful waiting game for many and can't really be avoided if you want to be in the game properly. The one good thing about Q/H tanks is that if they mini-cycle on you at least its really easy to change a lot of water!

The fishless cycling of a littler volume won't be any different than the big volume. You follow the Add&Wait method in our main article. You don't want to add ammonia more than once a day and only then if ammonia has dropped all the way to zero at some point in the preceeding 24 hour period. Your goal, a month or two down the road, is for both ammonia and nitrite(NO2) to drop from (4ppm we'll say) full concentration down to zero ppm within 12 hours of when the ammonia was added. At that point you know you are close and can start your "qualifying week." For the better part of that (hopefully) last week, you keep testing and adding ammonia and watching it perform its trick in less than 12 hours and make sure it hasn't "fooled" you. Meanwhile of course you are making final plans with the LFS to be sure the fish for your first stocking group are really going to be ready for the day of the big water change.

Sponge filter, small internals or small HOBs are common for Q/H tanks, so presumably that's what you'll be cycling. Sometimes the cycle can get a bit "flakier" in its feedback signals if the biomedia volume of the filter is extremely small, just because the bacteria can't find enough surfaces to form a very big colony.

~~waterdrop~~

 

[coldcazzie]

Right ok, I'll stick with 4ppm then.

Yeh I have a homemade filter - top cut off a water bottle then filled with 2/3rds gravel and 1/3rd sponge in the top, with a canabalised air in/out bit from an old sponge filter. It was either that or buy a new filter, and frankly, I don't have time to wait til I have enough money to spare (v.limited income!)

 

[waterdrop]

How far along are you on the fishless cycle of the big tank? It could be that you might reach the end of that, do a first large stocking and go for a bit not yet needing your Qtank. You could be coming along with the fishless cycle of the Qtank, with it being farther behind in schedule, and then grab a little bit of media from your big tank late in the game just prior to needing to quarantine some fish intended for the second batch.

~~waterdrop~~

 

[coldcazzie]

I'm not. I already have 2 angelfish, have had this tank for about 3.5 years now and have had all sorts in it, but went through a disaster patch where all my fish died, then I was given 3 angels a port hoplo and some kind of plec from a friend of my mums and that's all I've had for just over a year. 3 of them have died since, and I'm left with 2 angels and a tank that's looking incredibly empty!!

However, having had ongoing problems with putting bought fish in my tank (for a while now) I thought a QT would be a wise move, as I can't tell if it's an issue with bad stock from lfs or a water quality related problem. Or both.

Have set up the tank, conditioned water, done start up tests and dosed with Ammonia. Although I had to put rather a lot in - I used the aquarium calculator link at the top of the forum but the amount it told me to put in (1.25ml) only raised it to 1ppm not 4. So then I put another 3ml, and that raised it to just over 2ppm. Gonna wait til morning and dose again if it's still not risen - thought it might be a mixing issue?

Also came across another weird problem though - I have an API pH test kit, and also a Nutrafin Wide Range pH kit. The API test kit gave me a pH reading of 7.4 - same as my tap water. The Nutrafin one gave me a reading of about 6.5.

Nitrite - 0, Nitrate - 0, GH - 7, KH - 5. Temp is currently about 82.

 

[waterdrop]

Oh, ok, so you still don't feel you can steal any media from the big tank to seed the Qtank?

You are wise to let the ammonia mix a little more and see again what level reading you get, sometimes it takes a bit, like an hour or so, for the numbers you'd get to stabilize. If it still seems low compared to the calculator then you should probably chalk it up to the fact that once you uncap aqueous ammonia, the ammonia (which is of course a gas in its natural state, not a liquid) will begin to drop below the 9.5% or whatever was nominally marked. So in practice its often quite a bit weaker and that may be what you're seeing. It just means you'll be squirting in a larger amount than the calculator said and ammonia is cheap once you find a source.

Have you had access to good liquid-reagent tests and info over the years of the tank history you're describing? Always interesting to hear a tank history like that. Yours rings very true sounding.. wacky stuff happens, like people begging you to take fish you don't need but sort of have to for the sake of the fish!

~~waterdrop~~

 

[coldcazzie]

Oh, ok, so you still don't feel you can steal any media from the big tank to seed the Qtank?

I would, if it weren't for the fact that it's just finished (I hope!) a mini-cycle after I took a carbon pad out of it last weekend. Don't really want it to start another one by taking more stuff out!

You are wise to let the ammonia mix a little more and see again what level reading you get, sometimes it takes a bit, like an hour or so, for the numbers you'd get to stabilize. If it still seems low compared to the calculator then you should probably chalk it up to the fact that once you uncap aqueous ammonia, the ammonia (which is of course a gas in its natural state, not a liquid) will begin to drop below the 9.5% or whatever was nominally marked. So in practice its often quite a bit weaker and that may be what you're seeing. It just means you'll be squirting in a larger amount than the calculator said and ammonia is cheap once you find a source.

I went to bath/bed the kids inbetween adding and testing - am gonna wait until the morning and test again, and add some more if it's still not up to 4ppm. Apparently the bottle only cost about £1.50, so you're right - it's not like it costs the earth!

Have you had access to good liquid-reagent tests and info over the years of the tank history you're describing? Always interesting to hear a tank history like that. Yours rings very true sounding.. wacky stuff happens, like people begging you to take fish you don't need but sort of have to for the sake of the fish!

Good tests - yes, I've had these kits for a while. Although I only bought the pH, GH and KH kits about 2 weeks ago.

Good info - no. But I only realised that once I found this site lol (hence the comment about my ignorance in my sig!!) The fish all died due to the thermostat going in my heater (grrr!), and I actually got 6 fish off my mums friend (she specialised into just discus) but the silver shark jumped out of the tank during transport and didnt recover from the shock. I didn't mind rehoming them after all mine snuffing it - it was nice to have some bigger fish in there having only had smaller ones before (the biggest I'd managed was a juvenile CAE - so around 3 inches), plus it meant I didn't have to spend anything to restock.

But no, not good info really. The books I have on fishkeeping, while having excellent large sections on different types of fish, all teach fish-in cycles (being that they are about 15 years old!). The local shops have been rather hit and miss in the advice...maybe some of that was my inexperience, but I get the impression some of it has been either due to their incompetence, thinking I'm too stupid to understand what they're on about, or being too focused on business to give a sh*t about the fish...

Any ideas about the differences in pH value from the two test kits?

 

[waterdrop]

I would, if it weren't for the fact that it's just finished (I hope!) a mini-cycle after I took a carbon pad out of it last weekend. Don't really want it to start another one by taking more stuff out!

I should have rememberd that!

Any ideas about the differences in pH value from the two test kits?

Nope, your guess is as good as mine!

~~waterdrop~~

 

[coldcazzie]

I'll let you off, just this once!

Was quite excited about lack of ammonia today in my rio. Although no sign of nitrites yet. My back is enjoying not having to do a water change today!

 

[waterdrop]

Hey! I'm just a "re-beginner" like you.

With a nice big Rio, have you researched Pythons or similar DIY systems or similar things for hosing the water into the tank? I've got various Python system parts and they really help with water changes.

~~waterdrop~~

 

[coldcazzie]

Ok, so I tested again this morning, ammonia was still at 2ppm (was hoping it had risen during the night), so I added more (about the same that I added yesterday) at about 9.10am, left it, came back this aft and tested again, and it was still at 2ppm.

Tested nitrite, that was 0, so now I'm very confused at how I can add that much ammonia and not have it above 2ppm

Any ideas?

ETA: and no I haven't - a few weeks ago I was so frustrated with the whole thing that I was ready to sack it in, give the fish away and sell the tank, but hubby talked me out of it so I've kinda thrown myself in at the deep in, found this place and am kinda stunned at how much I didn't know. To be fair tho, it's a rented house so there's a limit to what I can do. When we buy I will definitely be installing something more permenant.

 

[waterdrop]

No problem. You just haven't worked out how strong your ammonia is and therefor how much to put in to get a given concentration in the tank volume. You can reassure yourself perhaps by putting one drop of the pure ammonia in your ammonia testing tube and then adding water up to 5ml... when you test that I'd expect it to be at whatever the highest possible reading is for your test kit. Then I'd go from where you left off before, adding an amount that a little larger yet again than before and this time I'd not wait so long to test.. perhaps just 20 min or something and see if we can't see it going higher than 2ppm. You're going to just have to keep experimenting to discover what it takes.

If you wait long periods before testing then the process can fool you. There will be a very small number of ammonia eaters in there but they may indeed have processed some of the ammonia into nitrite(NO2) and then a very small number of nitrite eaters may have processed -that- on into nitrate(NO3) and I don't think you've been posting any nitrate(NO3) test results so far.

The good thing is that you can be doing all this "experimenting around" to figure out your amounts/concentrations and all the while (since there is ammonia circulating in there and its somewhere around 2ppm (which is more than zero ppm and less than 7 or 8ppm which is all we care about) we will have been stimulating the growth of the ammonia eating bacteria all along, day and night.

~~waterdrop~~

 

[coldcazzie]

Yeh I didn't test nitrate yet as I thought it was unlikely to have got that far in the process. I know there is something in the filter because the gravel in it is from my rio, so that will contain some bacteria (not a lot I know, but some) plus it was sitting in the rio for 3 days while the rio was doing its mini-cycle. I just didn't think there would be enough for it to have processed that much ammonia that quickly. Maybe I'm wrong!

Have spent all day today wallpapering and paint shopping (all indirectly QT inspired!), but am childfree tonight so will get all the test kits out with a pen and paper, do some experimenting, see what happens and report back. Will start a new thread though with all the details.

 

[waterdrop]

Yes, I'm prepping for wallpapering too, ugh!

I always advocate having an aquarium notebook and logging daily notes. Its amazing how useful those notes are later on.

~~waterdrop~~