• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

Marine tank converted to freshwater

charliek

New Member
Joined
24 Nov 2022
Messages
10
Location
Stroud
Hello folks, and thank you for the warm welcome and wise words so far! My past experience of maintaining a journal has been... varied, but I intend to do my best, so here goes.

20221214_135411.jpg

I've been running an AquaOne Minireef 180 marine tank for a while, with upgraded lights and skimmer, supporting a mix of SPS and LPS corals and assorted fish and invertebrates (and, from time to time, a more flourishing colony of assorted algae than I'd like).

Work and family commitments mean that the high maintenance demand of saltwater was becoming more of a drain on my spare time than I'd like, so I've reverted to freshwater. I say 'reverted' because, years ago, I kept a community tank which I loved: I was crap at plants, but great at breeding mollies and snails :happy:

So.

My salty menagerie has been re-homed to people with more time and money than I. The whole tank stripped down and cleaned of every trace of salt, coralline algae, and spirorbid worms. The skimmer has gone, and I've glued extra baffles into the sump to accommodate filter sock, filter floss, then alfagrog and fluval biomax. I've kept my carbon reactor and return pump but removed the powerhead.

I've also kept the lights, but re-parametered them for a six-and-a-half hour schedule of whiter light with dawn and dusk - I've also dialled the power right back: I think I'll be low light, no co2, slow growth for a while.

1671040886419.png

I've also planned a simple hardscape and light planting: Vesicularia Montagnei 'Christmas', Anubias Barteri var. Nana, and Microsorum Pteropus 'Narrow' for now. Bogwood and inert rock and substrate (I don't plan to plant in the substrate)

I'm cycling with ammonia and, following the advice of @dw1305, popped the plants in already.

Since 23rd Nov, a 4ppm ammonia load has reduced to 0.4, nitrites risen to 1ppm, and nitrates to 60ppm - so cycling is starting. Some of those nitrates will be attributable to a 10ml dose of TNC complete for ~200ltr water - (a deliberately light dose, given low biomass and light).

Once cycling is complete, the stock plan is a pair of Electric Blue Acara, a small shoal of Lemon Tetra, a few Otocinclus, and possibly some nerite snails and cherry shrimp. I've seen some small signs of green algae on the bogwood, and grey wispy algae on the Anubias - the latter was easy to wipe off with a finger, and hasn't returned and meanwhile the plant has greened up somewhat. I suspect this is normal cycling balance stuff - at least I hope so.

20221212_111800.jpg

Next, I plan to get my head around the whole plant nutrient thing. I don't want to keep buying expensive water but, frankly, I'm finding the whole body of knowledge on dry salts, macros, micros, dosing calculators, etc. to be quite voluminous and - sometimes - a little inaccessible. I expect to get there in time, but don't be surprised to find me elsewhere in the forums with questions.

Lots of questions.

If we don't speak before, I wish you all a very happy Christmas (or whichever way you prefer to celebrate a circuit of the sun)!

Charlie
 
Hi all,
I'm cycling with ammonia and, following the advice of @dw1305, popped the plants in already...Since 23rd Nov, a 4ppm ammonia load has reduced to 0.4, nitrites risen to 1ppm, and nitrates to 60ppm - so cycling is starting.
I'd stop adding the ammonia, it won't help "cycle" the tank and it may well lead to a really large algae bloom now you have the plants in, <"nutrients added"> and <"the lights on">.

The traditional view of cycling, and the <"microbes that occur in aquarium filters">, isn't right. Have a look at <"Dr Timothy Hovanec's comments about Bacterial supplements"> and <"Correspondence with Dr Ryan Newton - School of Freshwater Sciences, University of Wisconsin—Milwaukee">, (and the threads that led to them <"Bacteria in a bottle ?"> & <The nitrifying microbes in aquariums and cycling">) for some more discussion.
Vesicularia Montagnei 'Christmas', Anubias Barteri var. Nana, and Microsorum Pteropus 'Narrow' for now. Bogwood and inert rock and substrate
I would worry a little bit about the Anubias, they are prone to melting in <"high ammonia environments">.
Some of those nitrates will be attributable to a 10ml dose of TNC complete for ~200ltr water - (a deliberately light dose, given low biomass and light).
Could you <"add a floating plant?"> I'm a <"frogbit obsessive">, but <"any one would do">.

cheers Darrel
 
Last edited:
Thank you Darrel - and indeed on the basis of our previous conversation I stopped adding ammonia, and added plants instead 🙂

Today, ammonia was practically undetectable (JBL test kit). Nitrites and Nitrates, by contrast, are both up - so the ammonia is moving through the oxidation cycle.

I'm content that that implies that nitrifiers are multiplying in the ecosystem. I'm not in a rush to add fish - I'll wait until the nitrites are oxidised and, ideally, I'd then like to prove the nitrifiers.

Previously, I'd have done that by adding a small quantity of ammonia - say 2ppm - and measuring its progress through to nitrite and nitrate. Then big water change and fish (who will be my long-term providers of ammonia)

I'm happy to learn better ways of testing the nitrifiers/AOA if 2ppm NH4 is liable to melt my Anubias.

And finally, yes, I'm definitely after a floating plant - and I fancy either Frogbit or Salvinia (broad hints have been dropped with F.Christmas)
 
Hi all
Thank you Darrel - and indeed on the basis of our previous conversation I stopped adding ammonia, and added plants instead......I'm content that that implies that nitrifiers are multiplying in the ecosystem......
And finally, yes, I'm definitely after a floating plant - and I fancy either Frogbit or Salvinia (broad hints have been dropped with F.Christmas)
Because nitrate measurement can be problematic, I usually don't try and measure it and rely on the growing plants (and associated microbial flora) to deplete it.

It is a bit of an act of faith and I understand that some people are happier with some values.

You will need some faster growing plants. If Santa fails you PM me, I always have spare Salvinia & Frogbit.

Cheers Darrel
 
Nitrate looks sane and is behaving as I'd expect.

Nitrite is way up - 1.5ppm - which is higher than I'd anticipate given that ammonia is making it through to nitrate. I'm not sure to what extent dosing fertilizer skews those tests though.

More Anubias on the way, along with some Salvinia and Frogbit.

I'm looking forward to being able to put some fauna in, too...
 
Hi all,
along with some Salvinia and Frogbit.
Perfect.
Nitrite is way up - 1.5ppm - which is higher than I'd anticipate given that ammonia is making it through to nitrate. I'm not sure to what extent dosing fertilizer skews those tests though.
Strange. The fertiliser shouldn't make any difference with the nitrite (NO2-) test. Just a thought (and probably a silly one), is it a marine test kit? If it is? It it may be calibrated to take into account the chloride ions (Cl-) in sea water?

Nitrite forms coloured insoluble compounds, which means we can test for it relatively easily with colorimetric methods. One of the potential issues with nitrate testing is that you need to reduce the nitrate (NO3-) to nitrite (NO2-) with <"cadmium (Cd) or vanadium (V)">.
I'm looking forward to being able to put some fauna in, too...
Because of NO2- level I'd wait until the Frogbit and Salvinia are really growing well. @_Maq_ 's post may be of interest <"The nitrifying microbes in aquariums and cycling">.
1. I've made quite a many experiments relating to cycling new tanks. I've never detected comammox processes. Nitrite spike was always present. That does not imply necessarily that comammox microbes are not present in our tanks, yet it suggests that it takes quite a while before they develop.

cheers Darrel
 
Last edited:
Yur... can't think who suggested it 😎

Just a thought (and probably a silly one), is it a marine test kit?
Good thought, but no - it's a JBL Combi test kit, corroborated with an API Master kit. It's probably just ammonia oxidation moving through the nitrifiers - I expect a nitrite spike, but was just surprised that its not yet coming down now that ammonia is undetectable and nitrate seems to have spiked too.

Nitrite forms coloured insoluble compounds, which means we can test for it relatively easily with colorimetric methods. One of the potential issues with nitrate testing is that you need to reduce the nitrate (NO3-) to nitrite (NO2-) with <"cadmium (Cd) or vanadium (V)">
I'm learning loads here.

Because of NO2- level I'd wait until the Frogbit and Salvinia are really growing well. @_Maq_ 's post may be of interest <"The nitrifying microbes in aquariums and cycling">.
I'm in no real rush (aside from the usual levels of impatience!)

I saw that @_Maq_ post this morning, in fact. Fascinating. I love the fact that stuff is moving on and new knowledge is developing as we speak. My cycle has had no fish-food or other organics: just ammonia and, later, plants (which will have contributed some trace organic decay and possibly some microbes/bactaria/archaea of their own.
 
Hi all,
Yur... can't think who suggested it
I'm just a <"Frogbit fan"> and <"floating plant obsessive">.
it's a JBL Combi test kit, corroborated with an API Master kit. It's probably just ammonia oxidation moving through the nitrifiers - I expect a nitrite spike, but was just surprised that its not yet coming down now that ammonia is undetectable and nitrate seems to have spiked too.
Not at all sure, I think we'll have to go with its a valid result and its come from the oxidation of TAN (NH3/NH4+).

cheers Darrel
 
Not at all sure, I think we'll have to go with its a valid result and its come from the oxidation of TAN (NH3/NH4+).
I concur. It's the simplest, safest assumption.

OK, well the only way to be absolutely sure is to dust off and nuke the entire site from orbit... but it's definitely the second safest assumption.

edit: some worms
 
Back
Top