My freshwater planted nano tank project

[Dr Mike Oxgreen]

I've been away from fish keeping for a good few years, and I miss it. (I also miss keeping rats, but that's much harder to swing with Mrs Oxgreen.) So I've decided to set up a nano tank as a winter project. Mrs Oxgreen likes the idea too, so it's all systems go!

For me, an aquarium is as much an underwater garden as it is a container for some fish. In fact, I tend towards the "Dutch" style, where plants dominate and fish are merely a minor point of interest. So my aim is a mini Dutch-style aquarium.

I've been thinking a lot about what setup I'm going to create, and have settled on the following choices (I think):

• Tank: 24 litre - 40x25x24cm. To my mind, anything much bigger than this isn't truly a "nano" tank. "Nano" means "tiny", not just small.
• Filtration: External canister filter, possibly a Fluval 106. Any type of internal filter takes up valuable space in a nano tank, and is always more awkward to maintain. An external filter also very slightly increases the overall body of water.
• Lighting: 1300 lumens of 6,500K LED. This is probably equivalent to between 20-25W of compact fluorescent, giving about 3-4 Watts per US gallon. I want to grow some of the most demanding plants, so I need lots of light.
• CO2 injection, probably from a soda stream canister, with a solenoid valve so that I can synchronise it to the lights. I've used fermentation before, and it works - but you can't control it and it needs renewing every 10 days or so.
• Heating: I'm going to go for an external inline filter, so that there's as little equipment inside the tank as possible. Unfortunately that means I'll have to go for a 200W power, which is far too big really - so I intend to get a separate temperature controller (STC-1000) so that if either sticks in the 'on' position the heating will still be regulated by the other thermostat.
• Plants: I want a nice carpet of something like Glossostigma and/or Hemianthus micranthemoides. These are often rated as difficult, but I've grown them before under strong light with fermented CO2 and that seems to be the key. I love seeing bubbles of oxygen forming on tiny leaves! I also like hair grass, small cryptocorynes and something red/brown for contrast.
• Fish: Probably half a dozen chilli rasboras. Mrs Oxgreen likes suckermouth catfish, so probably an otocinclus. A small handful of cherry shrimp type things, but maybe in a bright blue colour for contrast with the rasboras. That'll probably be plenty of livestock. Too much? What do you think? The oto will need feeding, because there hopefully won't be enough algae for it.

This morning I ordered the CO2 kit and the lighting rig. I'll order the rest of the stuff later next week so that they arrive while Mrs Oxgreen (a teacher) is on half term and can receive the deliveries.

If anyone's interested I'll post up the occasional picture as the project progresses!

I can't wait to start getting geeky with aquarium kit!


Edited to add: My choices are not set in stone, so if you think I'm making a mistake or you have some other good ideas, I'm all ears...

Edited by Dr Mike Oxgreen on Sunday 18th October 19:20

[AlexC1981]

Yes please do update. I only have plastic plants in my tank because the plants kept dying and I was worried the decaying plants might be causing an excess of nitrates. I never really looked into how a CO2 set-up works, so I would find this interesting.

I have the Fluval 106 and the Hydor ETH 200W inline heater set up with my 64L tank. It seems to work well, but it would be a strong flow for a 24L tank even with the valve closed half-way, which is the most the manual says you should close it.

[AM7]

+1 for updates please!

As above, I've never had any luck with real plants as they tend to decay after 6 months and create a lovely mess.. I do love a natural looking aquarium though so am definitely interested

[otolith]

I've got a 40cm planted cube with LED lighting and CO2.

It could do with a bit of pruning!

[Dr Mike Oxgreen]

^^ Wahey - that's what I'm talking about! I like that bronze crypt.

Failure with plants is usually down to insufficient light initially. The lids of most aquaria do not provide enough lighting for good plant growth, and for that reason I'm avoiding any of the all-in-one nano kits so that I can choose all the components myself. I suppose it's a bit like buying hifi separates rather than a ready-made system.

Plants generally suffer from "limiting factors". The first limiting factor is usually insufficient light, but if you provide lots of light then CO2 becomes limiting and you need to provide that as well. The third thing to become limiting is nutrients: in a tank with lush plant growth the nitrate level will drop towards zero and you need to add nutrients. I haven't decided on my fertilisation regime yet; I've read about "EI" where you slightly overdose with daily nutrients and then do a big water change each week, but that sounds like a lot of work!

It's worth noting that plants do not like under-gravel filtration, but that seems to have fallen out of fashion these days.

I am a bit concerned that my filter choice might be too powerful. I'd like to mount it below the tank, so that will reduce flow. What filtration are you using, otolith?

Edited to add: Now considering the Eheim Classic 2211, which has a flow of about 300 litres per hour. Still generous, but probably sensible.

Edited by Dr Mike Oxgreen on Monday 19th October 07:24

[anonymous-user]

Looking forward to this, some of the dutch style tanks and aquascaping I have seen are jaw dropping.

Here are some of the 2014 winners of the IAPLC competition http://www.thisiscolossal.com/2014/01/the-incredib...

[otolith]

Dr Mike Oxgreen said:

^^ Wahey - that's what I'm talking about! I like that bronze crypt.

It's nice, but it's a thug. I ripped it all out last time I rebuilt the tank, and it grew back from root fragments. It needs frequent aggressive pruning. The grassy plant is Lilaeopsis novae-zelandiae, which seems easy to grow.

I have a 240 litre tank which I intend to rebuild at some point as a planted setup, using the plants from the cube.

[Dr Mike Oxgreen]

The equipment is steadily arriving. So far I have:

• The inline heater
• The CO2 kit, with bubble counter, diffuser, drop checker and soda stream canister
• The light

There was a comedy fire-extinguisher moment last night while I figured out how to connect the CO2 bits together. I lost a few litres of CO2 I think. But I've experimented with the bubble counter and solenoid and all appears to be working.

They've actually sent me a different light unit. The one I ordered was going to be slightly too big and would need some ingenuity to make it sit correctly on top of the tank. The one they've sent me isn't listed, but is smaller and will fit properly, and only 100 lumens less powerful (1200 instead of 1300) - so actually it's a much better choice. It should still be a nice high light level in this small tank.

The tank itself appears to be coming from Germany - one of the quirks of Amazon's marketplace! I'm also waiting for the filter (I went for the Eheim 2211 in the end), a lily pipe and a pair of electronic timers (one for the lights, and another for the CO2).

The first job will be constructing some shelving in the corner of the room to hold the tank and the equipment. Probably a job for next weekend.

[AlexC1981]

With a tank as densely planted as Otolith's above, do you still have to clean the substrate? I give mine a gravel vacuum weekly when I do the water change and get quite a lot of poo out from between the gravel by raking the tube through it, which would be otherwise rotting?

[otolith]

The hardest part is calibrating the CO2, because there is a lag between adjustments and output. Quite easy to fiddle with it and gas your fish.

[Dr Mike Oxgreen]

AlexC1981 said:

With a tank as densely planted as Otolith's above, do you still have to clean the substrate? I give mine a gravel vacuum weekly when I do the water change and get quite a lot of poo out from between the gravel by raking the tube through it, which would be otherwise rotting?

In practice you can't really, because there's nowhere to put a gravel vacuum thingy without sucking up some of the plants. The fish stocking level will be very small though, so hopefully most waste will break down naturally.

otolith said:

The hardest part is calibrating the CO2, because there is a lag between adjustments and output. Quite easy to fiddle with it and gas your fish.

Yes indeed. I plan to spend a while experimenting with the CO2 level before adding any fish or other animals. I want to see what sort of pH swing I get during the dark period when the CO2 switches off, and if necessary I might consider having a few CO2 'on' periods during the darkness to prevent the pH rising too much. I will also see what happens if I leave the CO2 on permanently during the darkness; hopefully it won't go dangerously high so that if the timer or solenoid fails it won't be a problem. I'm assuming that the rate of CO2 usage by the plants is much smaller than the rate at which CO2 is expelled at the water surface, and I'm also assuming that the fish won't contribute much to the CO2 level. It'll be interesting finding out!

[otolith]

Are you planning to use a pH probe? I monitor CO2 levels with a drop tester, but that relies on the indicator fluid, air space and tank water reaching equilibrium which is slow.

Re hoovering - I do have a suck around with a syphon tube when I do a water change, but access is limited.

Technically, I should be doing a weekly 50% water change to keep the fertilisers at the right level, but in practice it manages with less attention than that.

[Dr Mike Oxgreen]

otolith said:

Technically, I should be doing a weekly 50% water change to keep the fertilisers at the right level, but in practice it manages with less attention than that.

So do you use "EI" fertilisation, where you slightly overdose with daily fertilisation and then (supposedly) do a weekly 50% water change to prevent the levels rising? I haven't decided on my fertilisation regime yet; I'm probably going to try a less intense routine and see how it goes. I don't think I can be arsed with fertilising every day and water changing every week.

I hadn't thought about using an electronic pH meter, but now you've planted the seed in my mind, and I might end up spending even more money on this silly project. So, er, thanks!

After I've done this nano tank, I can see myself wanting to do a plants-only "pico" tank, probably using a florist's vase, with CO2 fermentation and no filtration.

[otolith]

I started off following an EI regime, yes, then moved to just the large water changes with start-up fertiliser levels.

I think it's more necessary while you get it established, once you have lots of healthily growing plants things seem more tolerant.

[marksx]

Now you are planting seeds in my head.

I have a nano tank going empty, which I was going to use for fry. But, I also have a basic CO2 setup doing nothing in the garage.... Hmmm

[Galsia]

otolith said:

I've got a 40cm planted cube with LED lighting and CO2.

It could do with a bit of pruning!

That looks amazing? What fertilizer do you use?

I can't get anything to thrive in mine.

[otolith]

I have a stock solution made up from these dry powders;



Plus Ferropol for iron and trace elements.

[Galsia]

otolith said:

I have a stock solution made up from these dry powders;



Plus Ferropol for iron and trace elements.

Ah I just use Ferropol at the moment. I thought that it was a complete plant food.

Where do you get it from and how do you know what ratio to use?

[otolith]

There is a calculator here;

https://www.thenutrientcompany.com/aquarium/calcul...

And they also sell the chemicals;

https://www.thenutrientcompany.com/product-categor...

I can't remember if that's where I bought them from, they last absolutely ages.

[Galsia]

Cheers. Having to add something 5 days per week is a bit nuts but I'll give it a go.