The office tank...a 5 gallon pseudo walstad

Hi everyone! I am setting up a 5 gallon 'pseudo walstad' planted tank for the break room at work and thought I would journal its progress. I will start by saying this tank is already not going according to plan...

My original plan was to use the dry start method to get Hygrophila corymbosa and Ludwigia 'super red mini' thoroughly established in the tank before I flooded it, thus minimizing the shock of transitioning from emergent to submerged life, and then adding some floating and/or strictly aquatic plants when I flooded the tank. Sunday I purchased those plants from a seller on Ebay, and they arrived earlier today...unfortunately the order was messed up instead of the Hygrophila I got hornwort and two Dracaena plants (the latter being a terrestrial plant not suitable for aquariums, the former being a strictly submergent plant not suitable for the dry start method). Not wanting to waste the hornwort, I quickly flooded the tank, planted the Ludwigia, and tied the hornwort to some pieces of PVC pipe while flooding the tank...here is the (relatively attractive) result;


The air powered filter was constructed the other day, but I only bought the pebbles to keep it weighed down today. The tank has a 575 lumen, 2700k BR20 led bulb (no clue on PAR, but this is the bulb powering my 10 gallon) set to be on from 7 to 11 am, off from 11 to 3 pm, and on again from 3 to 7 pm. As this is going to be a modified walstad setup I will not be siphoning much detritus or encouraging bacteria in the 'filter' (it will eventually contain some coconut coir, which will decay and add CO2 for the plants), but it will receive water changes on a weekly basis (I will likely do frequent water changes the first week or two to counter organics from the potting soil I used in this tank...the substrate is 25% potting soil, 75% pool filter sand). I have not decided on livestock aside from snails to aid with processing uneaten food and detritus (primarily trumpet snails, though at least one pond snail hitchhiked on the plants), but as this will be an office tank I will need to avoid fish that demand live food (the break room has a freezer, so frozen would be OK...suggestions for livestock would be great). Both my tap and the tap at work are very soft, so I added a mix of calcium chloride, epsom salt, and potassium bicarbonate that pushed the GH and KH to 8 and 6 degrees respectively.

Forgive my rambling...I will hopefully be able to get ahold of more plants for this tank (soon, ideally) and let it mature for a while before bringing it to work and (later) adding ornamental livestock. Thanks for reading

 

I have a 5 gallon tank on my desk at work. It's very low tech, with a light. No mechanical filtration or added air, just a lot of plants.

Currently it has just shrimp and snails, and I like it fine like that. I had a trio of guppies in it, but brought them home so I didn't need to worry about feeding while I'm out for the holidays, but I don't think I'll take them back. I might add a few endlers, or I might just leave it shrimp and snails.

 

Hi again everyone! Just a few small updates...I purchased some red root floaters online last night (they will be shipping Monday), moved four trumpet snails from my 10 gallon to this tank, and (this morning) fed the tank fish food for the first time. Not much else to report...

 

Hi everyone! Not a huge update...both the hornwort and the Ludwigia appear to be growing, and I added some tissue culture Cryptocoryne wendtii 'green' and Rotala rotundifolia to the tank (time will tell how they do in such a new tank). Here is a shot I took about two hours ago;

 

Hi everyone! I do not have a picture update at the moment, but I will give some updates...ammonia levels are currently at .25 ppm, the hornwort (which I had to trim extensively), ludwigia, and rotala are all growing well (hard to tell with the crypts), and I received some red root floaters wednesday that I placed in the tank. In that same order were the largest amazon frogbits I have ever seen...many of them were 3 or 4 inches across and did not fit in the tank, so I purchased a 18 quart sterilite storage bin, drilled some holes in it for ventilation and to facilitate water changes, and placed the frogbit in that with a light. When I get pictures of this tank Sunday, I will also photograph this 'QT bin' (which is surprisingly transparent and could probably be used as a display tank).

 

Hi everyone! Here is the promised picture update;


Not much has changed since the last update...though I will say the tissue cultured plants are not growing as vigorously here as in my 10 gallon. The Ludwigia is currently green and is not showing any evidence of turning red at this time. I sprouted a water lily I got at a nearby petco and set it in this tank...I set the tank up with a heater as well to warm the water to water lily friendly temperatures.

Finally, here is the 'frogbit bin';

 

Hi everyone! Not a picture update, but still important all the same...I have noticed that the ludwigia and rotala are growing awfully - the ludwigia is growing slowly with very long, spindly leaves, while the rotala is very leggy - and I think I have figured out why; the tank's PH. I add a generous amount of potassium bicarbonate to new water for this tank as a potassium source, and the 7 degrees KH added with it has pushed the tank's PH up to 8 or so - high enough that almost all the CO2 dissolved into the water (from the air and/or from organic decay within the tank) is being quickly converted into bicarbonates that those plants cannot use (the hornwort is growing like a weed, but it can use bicarbonates to photosynthesize; not sure how the water lily and the crypts will do long term under these conditions). Thus, I am planning to effectively reset this tank to a much lower PH - perhaps as low as 6 - to facilitate the growth of plants that cannot use bicarbonates very well, and move the hornwort elsewhere. (I am encountering a similar problem in my 10 gallon, and once I move my persian killifish male will likely take similar measures there).

For those curious, here is a chart I found discussing the above relationship between CO2, bicarbonate, and (at very high PH) carbonates;

 

Hi everyone! It has been a LONG time since I posted an update on this tank...here is the tank as of this morning;


I have begun using a new salt mix that is devoid of bicarbonates, so the PH is now about 6.5 - far more congenial for plants that cannot use bicarbonates (the GH is 9 degrees...there is no good reason to lower it in this tank). I tossed the hornwort around the same time that I started using the salt mix, as not only was the hornwort unsightly but I also assumed that it would not thrive in an acidic tank.

You may notice that there is no longer a filter in this tank...I had created a new bottle filter for this tank, but it did not fit very well in the tank and kept knocking the lid off (thankfully the NiCrew SkyLED plus was never on top of the lid when this happened, as it is not completely waterproof). The last time this happened Wednesday the 9th, I flew into a bit of a rage and removed the bottle and all aeration entirely, instead setting up a ring of flexible tubing to keep the frogbit out of the middle of the tank (thus allowing light to reach the submersed plants). Later that day the underside of the water lily's leaves were covered in oxygen bubbles for the first time in this tank's existence...so apparently that was not a bad idea, even if it was more impulsive than I would like. Based on the drop checker, CO2 levels for at least part of the day are 10-12 ppm (due to organic decay of the substrate and the bag of coconut coir in the back right of the tank).

Finally, Thursday I got a very generous order of plants from Dustins Fishtanks...big shout out to them, by the way . Anyhow, I got Ludwigia repens, Hygrophila difformis, and Alternanthera Lilacina, all of which are now planted in this tank (I got more H. difformis and L. repens than I could use...I have not figured out what to do with the excess yet, so they are floating in my 10 gallon). I would be very upset if the Ludwigia and Hygrophila do not thrive in this tank, but the Alternanthera is a bit of a gamble...

 

Hi everyone! I just did some trimming and a water change on this tank...here is what it looks like as of a few minutes ago;


I removed the leggier lower sections of the Alternanthera and the Ludwigia (they came leggy looking...they do not appear to be growing in a particularly leggy fashion, though the Ludwigia is not turning red thus far) and thinned out some of the frogbit. No sign of algae yet...remarkably, in spite of the lowish PH and the lack of bicarbonates, the snails still appear to be surviving and possibly breeding (I have occasionally seen snail eggs on the side of the tank). Time will tell how they do long term.