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Dark start worth the time?

ElleDee

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I am very familiar with the theoretical benefits of doing a dark start, but it have also heard that it won't confer any real advantage over a regular plant-in fishless cycle with all the right boxes ticked (enough plants, appropriate light, and frequent water changes, etc). What is the current thinking on this?

If it makes any difference, this would be a low tech tank with contrasoil and some of the plants would be coming from my well established tanks, but other things would also need to convert to immersed growth or at least adapt to my specific conditions.
 

MichaelJ

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I am very familiar with the theoretical benefits of doing a dark start, but it have also heard that it won't confer any real advantage over a regular plant-in fishless cycle with all the right boxes ticked (enough plants, appropriate light, and frequent water changes, etc). What is the current thinking on this?

If it makes any difference, this would be a low tech tank with contrasoil and some of the plants would be coming from my well established tanks, but other things would also need to convert to immersed growth or at least adapt to my specific conditions.

Hi @ElleDee I would like to know that too.

As far as I understand dark start essentially means adding substrate, hardscape and water, filter/heater etc. and let it sit for a while without light (and perhaps adding some bacteria in a bottle, some mature soil or filter material)? I don't see how it would necessarily hurt, but I also don't see much benefit from this compared to just letting the tank reach its temperature, clear up and add a ton of plants right away and wait for the tank to mature and wait until your seeing some good growth before adding livestock.

Cheers,
Michael
 
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Wookii

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The traditional idea behind a 'dark start' is that you run the tank without lights, and with a low level source of ammonia, for a period of time until the filter is sufficiently populated with nitrifying organisms without the risk of developing algae. In a planted tank that is unnecessary.

The one valid reason to run a 'dark start' on a planted tank - and the one case when actually I would recommend it - is if you are using a soil which releases high levels of ammonia. You run the dark start for a week, maybe two max, do a few large water changes until all the ammonia is flushed out, then drain, plant and run as normal. This stops high levels of ammonia potentially damaging young and/or sensitive plantlets that haven't established yet, such as invitro plants and Buce etc saving a lot of lost money on melting plants. That said many people just plant straight away even with high ammonia soils, and just do very large daily water changes without major issues - it just depends how safe you want to play it.

If you are using an inert substrate, or one that doesn't release large amounts of ammonia, you can just plant straight away and run as normal with a few larger water changes in the first week or two as normal for a tank start up.

I've not come across the Controsoil before, but it claims lower levels of ammonia: Substrate – Ultum Nature Systems so the choice is yours.
 

MichaelJ

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is if you are using a soil which releases high levels of ammonia
Good point @Wookii ... Are there other ways to flush out excessive levels of ammonia?


If you are using an inert substrate, or one that doesn't release large amounts of ammonia, you can just plant straight away and run as normal with a few larger water changes in the first week or two as normal for a tank start up.
Thats what I would say as well.


Cheers,
Michael
 

Wookii

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Good point @Wookii ... Are there other ways to flush out excessive levels of ammonia?

Some people have done it in buckets before hand I believe, but to me that sounds like more effort than its worth and will be tricky on a larger tank. I'd personally just scape the tank, fill it and water change the ammonia out - it also allows you to make changes to the scape (which always ends up looking different once the water is in) when you drain it without having to disturb any plants.
 

ElleDee

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Thanks @Wookii, that makes total sense. I had not considered doing it for less than a full cycle, but a week or two sounds perfect. I'm also going to be submerging a piece of driftwood for the first time also, so even if the soil isn't dumping ammonia (we'll see if the reality matches the marketing), the tannins are going crazy.
 

foxfish

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Good point @Wookii ... Are there other ways to flush out excessive levels of ammonia?
Not flush out but use up perhaps ‘use up’ with a dry start?
Personally I cant think of a many things more boring and frustrating than watching a blacked out tank.
 
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ElleDee

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I may be wrong as I am not particularly familiar with contrasoil but I though that it did not contain ammonia anyway?
If that is the case, then you can just plant heavily from day one and let the plants cycle the tank.

The promotional materials say low ammonia release, so that implies that there is some.

Honestly, aquasoil retailers are probably skirting US laws in not disclosing any nutrients added to the soil. At minimum it's very annoying to me.
 

plantnoobdude

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I used a dark start (in a sense) when swapping out substrate for my already established main tank with stock. I chucked a bag of amazonia in some RO water and let it do it;s thing for 6 weeks. The day before I used it I did a big 95% water change on the bucket. still got some algae issues but no livestock stress which is what I was hoping for.
 

MichaelJ

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Honestly, aquasoil retailers are probably skirting US laws in not disclosing any nutrients added to the soil. At minimum it's very annoying to me.
I don't think this is a US law-thing by any stretch... I would love to hear about any country in the world that have laws that stipulates requirements to disclose the content of aquarium substrate! :) ... as an avid hobbyist i wish the producers of substrates would - same goes for fertilizers, fish food etc.

Cheers,
Michael
 
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Courtneybst

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I personally found it useful in my most recent setup. I didn't want to do daily water changes, I just feel it's an unnecessary labour.

I left the soil in position without lights/CO2/plants for 3 weeks and did one water change in that time (only to remove some slime). I drained and planted it and it was the smoothest setup I've ever done. Almost no water changes, barely any diatoms to speak of, the wood got a chance to saturate and leech out the tannins. I'd say it was a win win situation.

Edit: Also hardly any plant melt, including Cryptocoryne.
 
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ElleDee

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I don't think this is a US law-thing by any stretch... I would love to hear about any country in the world that have laws that stipulates requirements to disclose the content of aquarium substrate! :) ... as an avid hobbyist i wish the producers of substrates would - same goes for fertilizers, fish food etc.

Cheers,
Michael

So the US has a patchwork of regulations about fertilizer and horticultural growing media (which I think aquasoil falls under) labelling with the specific guidelines varying between states, but there's an organization that puts together the national recommendations. If you meet those, and they are honestly pretty straightforward, you are good to sell anywhere in the country. I just looked it up and the horticultural growing media rules are much laxer than I had remembered. They need to disclose the ingredients in the bag, but no guaranteed analysis of added nutrients, which I had misremembered.

However, your fertilizers should absolutely have a lot of details about what's in it and how much if you bought them in the US. Even specialty fertilizers like in our hobby are subject to these rules.

(The more you know ミ☆)
 
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