Mike's fish room musings

[dw1305]

Hi all,

The lower PO4 dosing mentioned in post #48 is not showing any effect - neither positive or negative.

It always takes a long time for phosphate (PO4---) deficiencies to show, because PO4--- is extremely mobile within the plant and it will continually be recycled it into new tissues until it really runs out. It also means that if you plants do become severely phosphate deficient, they perk up pretty quickly once it becomes available again.

Terrestrial plants <"show a characteristic purpling"> when PO4--- is deficient, but I'm not sure what happens with aquatic plants.

cheers Darrel

 

[MichaelJ]

It always takes a long time for phosphate (PO4---) deficiencies to show, because PO4--- is extremely mobile within the plant and it will continually be recycled it into new tissues until it really runs out. It also means that if you plants do become severely phosphate deficient, they perk up pretty quickly once it becomes available again.

Thanks Darrel. Yes, I always tend to forget which nutrients/minerals are mobile and which are not - which makes them critical for the plants not to run out of.

Edit. Now that we are at it. Here is a (definitive?) chart of all essential plant nutrients:

Note: Some sources list Silicon (Si) and Chlorine (Cl) as a Macronutrient - and some measurements from the Amazon basin seems to confirm its pretty readily available in tropical waterways:

Yup... quite a bit of Si and Cl even.

Cheers,
Michael

 

[MichaelJ]

Strategy to get Amazon Frogbit (Limnobium Laevigatum) to flower.... suggestions welcome.

I've been trying to "prevent" my Frogbit from just multiplying into numerous smaller plants thus quickly overcrowding the surface as opposed to individual plants just growing bigger and bigger and potentially get them to flower...I am not sure if flowering got anything to do with the age or the size of the plant though. My thinking and approach so far (for the last couple of weeding sessions) is to just keep on viciously weeding out the younger plants and letting the big ones alone. I do have some that have grown pretty big already.

This is what I want:

I would probably need to lower my water level a little bit.

EDIT: Darrel/@dw1305 kindly informed me (post #91 below) that the above flowering frogbit is Hydrocharis morsus ranae and not Amazon Frogbit (Limnobium Laevigatum) which I (probably) have, so the flower would look more like this:

Cheers,
Michael

 

[ian_m]

I've been trying to "prevent" my Frogbit from just multiplying into numerous smaller plants thus quickly overcrowding the surface as opposed to individual plants just growing bigger and bigger and potentially get them to flower...

This is what I got to keep my floaters under control. Works well.

Otherwise I end up with this....

 

[dw1305]

Hi all,

This is what I want:

That one is real Frogbit (Hydrocharis morsus ranae). I've seen it wild in the UK a few times <"European Frog-Bit (Hydrocharis morsus-ranae)">, but it dies back to a resting bud (turion) for the winter, which I think is also true of Limnobium spongia.

Both Limnobium spp. have a pretty underwhelming flower.

cheers Darrel

 

[hypnogogia]

This is what I got to keep my floaters under control. Works well.

and does that limit the extent to which they multiply, or two they start laying up on top of each other?

 

[ian_m]

and does that limit the extent to which they multiply, or two they start laying up on top of each other?

Yes it does limit the extent the floater can take over the surface. Obviously if doing weekly water changes, like one should be doing, it doesn't really get too dense as you pick some out each week.
However in the real world, especially in the run up to Xmas and holidays, my tank is running much reduced hours, so I don't need to do weekly water changes, the floaters do tend to stack up and start overflowing.

 

[MichaelJ]

Hi all,

That one is real Frogbit (Hydrocharis morsus ranae).

Thank Darrel, I bet your right. There goes another dream And digging a bit deeper I noticed a lot of these look very much alike - what pictures do you need to positively identify the species of my Frogbit? I do believe they are Amazon Frogbit (Limnobium Laevigatum) and as you said the flowers are underwhelming.

Anyway, this got a nice flower and is supposedly American Frogbit - Limnobium Spongia:

Cheers,
Michael

 

[MichaelJ]

This is what I got to keep my floaters under control. Works well.
View attachment 198059

Hi @ian_m, Thanks. Back in the day when I just had a small amount I did corral them with some plastic tubing as you are doing... I guess my comment is more about cultivating fewer but larger individual plants. I actually don't have a problem having them covering a lot of the surface. As you can see from the picture below, it's just that I end up with a huge amount of small plants instead of fewer large ones. I suppose my strategy of just keep weeding out the small ones will eventually work out. Tedious though.

Cheers,
Michael

 

[dw1305]

.........Anyway, this got a nice flower and is supposedly American Frogbit - Limnobium Spongia:
View attachment 198075

The picture is definitely Hydrocharis.

Limnobium spongia has <"a spidery offering">, like L. laevigatum.

Cheers Darrel

 

[MichaelJ]

The picture is definitely Hydrocharis.

Geez... why can't any of these resellers just get it right...

Limnobium spongia has a spidery offering, like L. laevigatum.

... I think I'll just change my mind and say I actually want a spidery offering ... that solves it.

Cheers,
Michael

 

[MichaelJ]

Ok, perhaps this entry is more along the lines of Serious Scientific Answers to Absurd Hypothetical Questions (courtesy of R. Munroe of xkcd.com fame)...

... but with almost 14 inches of very fresh snow fall overnight...

... I was just a little bit too curious about the TDS of such clean fresh snow melt after it reached (almost) room temperature...

I was somewhat surprised how depleted it is... at 7 ppm (14 uS/cm) there is not much of anything in terms of ionic solids. For comparison, the water coming out of my RODI unit is 4-5 ppm (8-10 uS/cm), the distilled water I use for my Micro blend comes out at 0-1 ppm and interestingly, the few times I measured our rain water in the summer time (after lots of rain!) it comes out at about 20-40 ppm (40-80 uS/cm). I am not 100% sure why snow melt would be that much "cleaner", but I guess it might be seasonal due to more dust, pollution, pollen etc. in the air in the spring/summer/fall time.

Anyway, so for a years usage I would need 3200-3500 liters, if I would keep my current 11-12 days 35% WC schedule for my two 150L tanks... Unfortunately its probably impractical to store and maintain such a large amount of water in my heated garage... or maybe just say 1000 liters to cut down on the RODI waste water? ... I know some water butts can hold up to 1000 liters (perhaps more...). Wouldn't I need to filter or treat the water - possibly over AC to keep it viable for that long? I suppose I could chlorinate it lightly to avoid any pathogens to get a foothold in the water butt and use Prime to "remove" it before I use it in my tanks.

Cheers,
Michael

 

[mort]

I'm guessing if you measured just the first snow the tds would be a bit higher as it would clear some particles from the atmosphere as it fell. Heavy snow is likely to have a lower tds for the same reason. I think it has a lower tds than rain because it's frozen in the atmosphere before falling.
I did a mountain winter survive course and we were told to remove the top layer of snow because it can suck up nasties even at high altitudes. This was on piddly little mountains inthe uk (the Carnedds in North Wales) but it's true in all mountain environments apparently, there is just nowhere anymore that humans don't influence.

 

[dw1305]

Hi all,

I was somewhat surprised how depleted it is... at 7 ppm (14 uS/cm) there is not much of anything in terms of ionic solids.

It is because it isn't the first snowfall you've had recently. Snow is very efficient at sweeping particles from the atmosphere. Edit What @mort says.

cheers Darrel

 

[MichaelJ]

It is because it isn't the first snowfall you've had recently.

True, we had quite a bit of snow already over the last week and the blizzard two nights ago in my area gave the most we had in a day this season.

Snow is very efficient at sweeping particles from the atmosphere.

Heavy snow is likely to have a lower tds for the same reason. I think it has a lower tds than rain because it's frozen in the atmosphere before falling.

Thanks to both... Yes, that makes sense. I am going to do a couple of measurements over the winter to monitor the variation.

Cheers,
Michael

 

[MichaelJ]

Duckweed "infestation"... Ok, today I noticed that my duckweed was getting to the point where they are starting to strangle my Frogbit!

I call this duckweed soup.... Notice some of the frogbit are looking below par with spongy yellowing leaves that I otherwise only see occasionally - not good and not what I care to accept.

Step one. Net out everything from the surface:

Step two. Clean up the residual duckweed from the surface using a wide net (as much as I could):

Step three. Wash off the duckweed from the Frogbit in the sink under running temperate water (not perfect but pretty clean):

This is how much I removed - including lots of Frogbit that just didn't make it back home

Step four. Put the clean Frogbit back in the tank!

I actually do this on a regular basis, but this might be the worst duckweed to frogbit ratio I've seen so far. It just might be that I have been removing too much of the frogbit over the last few months without removing an equal/balanced amount of duckweed

Anyway, I was reminded of something today (paraphrasing): Duckweed pulls a knife, you pull a gun. Duckweed sends one of your Frogbit to the hospital, you send all of them to the morgue.

Cheers,
Michael

 

[Hanuman]

Duckweed... that thing is a b**** the day you want to remove it. I remember it took me a good 6 months to remove it completely from my outdoor pond. There would always be a plant or two left that would restart the whole thing again.

 

[Myrtle]

I start all my tanks with duckweed; sometimes it stays as the only floater, other times it's replaced by something else. I dare not count the hours I've spent with tweezers, picking out the random surviving leaves before they multiply!

 

[AlecF]

Duckweed is the dust of the aquarium.

 

[MichaelJ]

Been a while since I posted anything to my Journal... Sooo...

Now that its getting warmer here in Minnesota making shipments of plants out of California temperature-safe, I am redoing my 150L (40 US Gallon) low-tech lean experiment tank with a new batch of stem plants. Yes, I still call it my lean experiment tank as I still have to see the glory of it with more challenging stem plants... 🧐

The scrawny stem clippings I bought a year ago when I started the experiment didn't make it. I think in part because of the less-than-ideal state the plants were in when I received them and in part because the tank had not fully made the "switch" to lean and I was sort of dithering between various remineralizing and dosing regimes, so this time around I hope for more success given the tank is now very stable and I am going get some nicer - and possibly potted - plants instead (i.e. I am prepared to spend some money this time ).

I am looking for 3-5 different kinds of slightly challenging stem plants - ideas welcome! - nothing crazy challenging and I am planning (hoping) to keep my water parameters, very lean dosing and rather laissez-faire maintenance routine that I have come to believe works well for densely planted, lightly/medium stocked low-tech tanks - in my case 35% WC every 14 days.

I am going to get rid of a bunch of plants already in the tank - all very healthy and mostly in the easy category - an obnoxiously large and very healthy java fern, some large sword runners, crypt and tons of floating plants are all on the chopping block - I am probably going to send them all out to a friend.

The tank is currently running like this:

NO CO2 injection

Mechanical filtration (sponges and occasional purigen in my 2 HOBs)
Internal PatMini for extra flow and aeration.
Dedicated UV filter (9w).

RODI WC water remineralized to GH 2.5 / KH 0.5
Ca 9 ppm from CaSO4 (5 ppm) and CaCO3 (4 ppm)
Mg 5 ppm from MgSO4 and Tropica Specialized

Dosing every ~14 days after WC with Tropica Specialized (targeting the full 150L or the WC water only...):

N 1.25 ppm (NH4NO3)
P 0.1 ppm
K 1.0 ppm
Fe 0.07 ppm

+ whatever N & P I get from food waste, 2 Oto's, 6 Bleeding heart tetras, 7 Rummy nose tetras and a pair of Angle Fish that are outgrowing the tank

Photoperiod is ~12 hours a day at medium light
Inert but mature (~3 years old) substrate (gravel)
Temperature ~22 C.
24/7 aeration.
Mostly excellent flow/circulation around the tank.
pH ~6.2
ORP ~350 mV

Except for a few tweaks here and there along the way (mainly the Potassium dosing, that I recently lowered vs. my Mg dosing and CaCO3 for KH instead of K2CO3), this is how the tanks been running for about a year now. Virtually zero algae, very clean, good plant health and growth albeit slow, but all mostly easy plants as mentioned above.

Cheers,
Michael