Saturday, 2 September 2017

Cryptocoryne cordata var. siamensis "Red Giant"

Cryptocoryne cordata var siamensis 'Red Giant'
I was lucky enough to score a piece of this Crypt from a local shop display tank.  I normally use small 95mm square pots for my crypts but this was a big crypt so it went in a  150mm pot and is in a 600l 6x2x2 tank (sharing with some purple spotted gudgeons).  Its a big crypt -  currently 40cm tall and the biggest leaf blades are 20x7cm excluding the petiole.  A few sellers in Australia recently have been selling a  Crypt cordata named "Red Giant" so I'm assuming this is the same - the undersides of the leaves are very red.  There are a few other similar plants in Australia at the moment: A Crypt cordata distributed by Dennerle, and another Dennerle variety sold as Crypt. x purpurea but clearly both are varieties of Crypt cordata var. siamensis.

  "To make a long story short: almost all Cryptocoryne cordata plants in our aquaria today belong to var. siamensis. If you have it growing successfully in your aquarium there is a more than 90% chance that it is var. siamensis. And even if it is not growing well, there is probably still a more than a 90% chance that it is var. siamensis. If it were one of the other varieties of Cryptocoryne cordata it would most likely be dead by now.  Of course, if you are one of the few people keeping aquaria with a pH of 4 – 5, you may have something else, but even then there is a good chance that you may have var. siamensis."

Jacobsen, N., and Bastmeijer, J.D. 2014. On Cryptocoryne cordata var. siamensis. Aquatic Gardener 27(3): 29–39.

Friday, 1 September 2017

Cryptocoryne ferruginea update

Quite a disappointing  recovery so far but fingers are still crossed for success.  One stem has rotted without shooting.  The other stem threw a couple of leaves then stopped and also rotted (the big leaf), but the other end of the stem has now shot again so fingers crossed.  The media is plain peat moss and sand watered by rainwater (pH 5.5 to 6.0) to provide acidic conditions.  I put some alder cones in the water to push the pH down a bit lower but they don't seem to have much effect.  I've tried oak leaves and beech leaves so far but still only getting pH down to 5.5 to 6 and I think I need to push it a bit lower (more acidic).

Cryptocoryne aura

Discovered in 2014 and described only last year. 
Has beautiful pink and green hues with a very fine transparent "frill" on the leaf margins.  So far it seems to grow well with the water just lapping at the leaves. Pictures of Crypt aura in its natural habitat show it growing in shallow water (Russian Blog

Thursday, 11 May 2017

Cryptocoryne ferruginea needs a helping hand

Crypt ferruginea stems re-shooting in the ICU

A couple of decomposing Crypt. ferruginea stalks were given to me in the hope that I can pull them back from dead.  Hopefully not too little too late.   I know nothing about C. ferruginea other than what I can find online.

From Ipor et al (2006), it is naturally found in acidic conditions with pH 4.6 to 5.5, likes very soft water and shaded conditions.

 I loosely bedded the stalks into a mix of sand and composted oak leaves and flooded them with pure rainwater (pH 5.5-6.0, EC 10-20 ┬ÁS/cm) to the depth you see here.  There is a bit of soil in the leaf mix that is initially causing the pH to rise, so I've been draining the pot and reflooding with fresh rainwater every couple of days to maintain acidic conditions.  I'm waiting on fresh supplies of peat moss and I may switch them over to a fresh mix with more peat if the pH keeps going up.

Fingers crossed.

Further reading: Ipor, I. B., C. S. Tawan, and M. Basrol. "Growth pattern, biomass allocation and response of Cryptocoryne ferruginea Engler (Araceae) to shading and water depth." Journal of Bioscience 17.2 (2006): 55-78.

Tuesday, 9 May 2017

Cryptocoryne parva submersed vs. emersed

Crypt parva (submersed)

Cryptocoryne parva is a great small crypt from Sri Lanka that is sometimes grown as a carpeting plant in a planted aquarium. Hats off to anyone that achieves this as Crypt parva is a very slow grower so you need patience or to invest in buying lots and planting heavily at the outset. I've seen people closing down a tank sell chunks of "carpet" afterwards for $100+ to be snapped up by the impatient.

The top photo is a slightly manky lunchbox of Crypt parva in one of my tanks. I plant parva around the base of my Aponogetons as it looks good and stops the fish scattering the gravel.  Some people think the Crypt roots help oxygenate the substrate.  Perhaps thats true... but in this case the Aponogeton died leaving me with a nice crop of parva about 1cm tall.  I took a few plants and put them in a pot to grow emersed and they took off.

Crypt parva emersed

If you didnt know better you might think the emersed plants are one of the Cryptocoryne ×willisii group that is well known for the characteristically lanceolate leaves on long petioles, or even a dwarf sagittaria. The substrate mix is nothing special - sand, peat moss, and a handfull of shell grit to buffer the pH and add calcium and a handful of composted oak leaves for nutrition

Last year I lost my emersed Crypt parva in winter - tough love in a cold climate. This year the heaters are in early.