After three weeks of treating the Shrimphaus with Tetra AlguMin in an attempt at chemical control of black beard algae, I can confidently report that monolinuron, the active ingredient in AlguMin, has absolutely no effect whatsoever on black beard algae (BBA, black brush algae). The algae is as healthy and bushy as ever, does not scrub off even with vigorous rubbing, and may even have grown a little thicker. I can’t really tell whether monolinuron was effective against green algae, as that wasn’t a major problem and so I wasn’t paying careful attention. Certainly there was no visible green algae at the end of the treatment but there may not have been much in the first instance.
Black beard algae (BBA, brush algae) used to be a bit of a nuisance in the Fireplace Aquarium, but since switching to a high phosphate, estimative index dosing regimen, BBA and really all forms of algae have been pretty much a non-issue. Tanks need to sort their own equilibrium, and what works for the high-tech CO2-injected Fireplace Aquarium is not necessarily appropriate for the low tech Shrimphaus. In general I prefer to ‘live and let live’ within reason for algae in an aquarium but in the Shrimphaus BBA has got to the point where it’s hurting the plants and not looking very pretty either.
What to do about it?
It’s been more than four months since the Alternanthera reineckii ‘Rosanervig’ got planted in the Fireplace Aquarium, and whilst it seemed to be doing well initially, after 11 weeks things weren’t looking so great. I thought lack of light from overgrowing Bucephalandra caterina might have been contributory, so I did a massive epiphyte trim to restore light to most of the tank. That had very positive effects on the Cryptocoryne wendtii ‘Flamingo’ but didn’t really improve the alternanthera. There were floating fragments of what looked like otherwise healthy Rosanervig leaves and I have from time to time noticed some suspicious interest in the alternanthera from the amano shrimp. Some surveys of the interwebs suggests that amano shrimp eating alternanthera species is a known thing which could explain the observed damage.
As an experiment, I have shielded the top of one of the Alternanthera stems inside a mesh bag. The aquarium denisens haven’t particularly noticed, although I did see a cheeky amano shrimp sitting on the bag – it scampered when I tried to take its picture. We’ll do an updated report after a while to see how the bagged plant compares to its non-bagged counterparts.
Two week update: shrimp-proof bag fail
Well… it seemed like a good idea anyway. Whilst the shrimp-proof bag did keep the shrimp away from the alternanthera, the bag became a major breeding substrate for black beard algae and the plant inside the bag with no meaningful flow and no access to a cleaning crew did not thrive. Not only that, but I couldn’t get the bag off and wound up tearing the head off the plant in the process! Looking at it after the fact showed a few new leaves had sprouted so the plant was giving it a try.
That being said, in the ensuing carnage I did notice there was an alternanthera plant not in the bag that seems to be doing reasonably well, so I moved that over to the front of the aquarium and we’ll see how that does.
Ephiphytes on the mountain before and after trimming
The bucephalandra and anubias have both done really well, overachieved in a some ways in fact. The caterina at the top of the mountain in particular is close to the light and grew across to make an impressive sombrero hat that did a nice job of shading most of the aquarium below. This shading has been a challenge in particular for the new cryptocorynes on the right, nevelli at the back and wendtii ‘Flamingo’ in the front, but also I suspect for the Alternanthera reineckii ‘Rosanervig’ over on the left side.
After repeated struggles to grow emersed plants on the Shrimphaus river using a variety of substrate set-ups, I’ve switched over to actual LECA – lightweight expanded clay aggregate. For this experiment, I’m going with two reputedly robust to low(er) humidity emersed growth anubias: Anubias coffeefolia, and Anubias gracilis. This is the second attempt with Anubias coffeefolia, but the previous go seemed encouraging, with some new leaves forming before ultimately the plant was done in by rhizome rot.
Adapting plants to grow in LECA
Although aquarium plants are generally grown in emersed form in the nursery, they are typically potted in rockwool in a near 100% humidity hydroponic ebb and flow environment. Transitioning terrestrial plants to LECA can be challenging and there are a lot of helpful resources with great tips available including to make sure every last bit of non-LECA substrate has been removed from the roots before planting in LECA. The process seemed straightforward but the plants started wilting almost immediately. It’s pretty well established that misting plants directly doesn’t meaningfully raise humidity so I did an improvisation with the conical plastic sleaves the plants shipped in. Cutting off the bottom of the cone to fit snugly halfway up the pot gave a large surface area on top that could be misted to both keep a lot of water droplets around for a reasonable length of time close to the leaves and to provide a locally semi-isolated environment. I kept the plants in the enriched humidity setup for three weeks, misting a couple times a day. That seemed to mostly do the trick to give the plants enough time to adapt to being rooted in LECA; the gracilis didn’t really lose any leaves to wilting, and although the new coffeefolia did lose half its leaves it seems to have stabilised (hopefully).
Repotting to get rhizomes out of substrate
Five weeks after planting, it was time to take the plants out of the LECA to see how the roots were doing and repot if necessary. Pretty much things were looking good, with healthy looking whitish roots with good structure. There were however some brown rotted aspects in places, in particular where the rhizomes had been embedded in the substrate. I used pinsettes to trim off those portions and gave the root systems a good rinse. Then I replanted taking care to have the entirety of the rhizomes out of the LECA. This meant essentially having the plants growing on the side relative to how they arrived in rockwool. Possibly an ebb and flow hydroponics system in the nursery is more permissive since plants can dry out during the ebb phase, compared to the steady-state semi-hydroponics method of sitting LECA embedded plants in the Shrimphaus river. The repotting process was easy and the repotted plants look good so far, but the real test will be whether the rotting stops and we start to get some new growth.
I’ve been looking for a red plant to replace the Ludwigia palustris mini ‘Super Red’ which is an awesome stem plant, but which comfortably exceeds 50 cm in length and so is really too large for the Fireplace Aquarium – keeping it trimmed was just too much hassle. Previously, I had a go with Alternanthera reineckii ‘Rot’ which started out promisingly, but then never really made a recovery after the usual ‘cut off and replant the tops‘ process. Further reading suggests that may have been where I went wrong – leaving the rooted bottom section to resprout new growth after trimming may have been a better approach with alternanthera, in contrast to approaches with many other aquarium plants. I’ll keep that in mind for the ‘Rosanervig’. Rosanervig is supposed to be an intermediate sized alternanthera growing to 20 cm or a little larger.
Adapting Alternanthera reineckii ‘Rosanervig’ to submersed growth
I received in from Pro Shrimp a quite large portion of Tropica-grown Alternanthera reineckii ‘Rosanervig’ potted in rockwool. Removing the rockwool carefully with pinsettes gave six healthy-looking emersed-form plants. I planted the Rosanervig in the middle left of the Fireplace Aquarium, in front of a developing back curtain of Vallisneria asiatica, and behind a foreground patch of Cryptocoryne parva. The emersed form leaves really aren’t very happy when fully submersed and several were shed straight away, or started developing some rattiness. Some of the amano shrimp may even have had a bit of a go at nibbling the straggly looking leaves.
Submersed form leaves start to look good after two weeks
After a couple of weeks, it’s clear that new submersed form leaves are developing nicely on the Rosanervig. Emersed form leaves are a blotchy light green with hints of red undertones on the top surface with pale pink/green undersides. In contrast, the submersed form leaves are deep red with bright pink veining structures on top and bright red/pink underneath. Previously the slow growing alternanthera had issues with algae collecting on the upper surfaces. Algae hasn’t been a problem since the revised estimative index dosing scheme was implemented in the Fireplace Aquarium so I’m optimistic for the Rosanervig’s prospects.
There’s an interesting new inhabitant in the Shrimphaus, what looks like a spontaneous mutation in the bloody mary shrimp lineage. Bloody mary shrimp are generally a solid translucent red throughout but this little fella (I think it’s a boy) is mostly clear and colourless, except for a red head, red stripe just above the tail, and one red horizontal back segment. This is the “rili” pattern, and is reasonbly easy to find in red cherry neocaridina shrimp, but there isn’t much information on ‘bloody mary rili’ shrimp. The eyes seem to stand out a lot more as well. I think this is because in the usual bloody mary shrimp the eye region surrounding the black pupils is reddish pink, whereas this googly eyed individual has completely white surrounding tissue.
Bloody mary neocaridina shrimp have a reputation as being reasonably genetically stable, so this seems a little unusual. I’ll keep a look out to see how this one develops – I’m not actually certain it is a bloody mary shrimp – and whether any more different and interesting mutants come up.
It’s been difficult with the emersed plants on the Shrimphaus shelf. Some descriptions of the tribulations below.
Growing on the slate surface directly (doesn’t work)
First I tried simply tying Chirstmas moss down in the flow on the riverbed to see if they would grab onto the river bottom, but that didn’t really work – it seems they need something for the roots to hang onto. Even though Christmas moss roots can grab onto surfaces, they didn’t do that in this context and the green parts didn’t really thrive either. I’m now growing Christmas moss completely submersed in the Shrimphaus and it seems to be doing reasonably well.
Clay balls roll away (doesn’t work)
So, this could have been obvious, but nearly perfectly spherical clay balls won’t say put in a swift-flowing water current. They all immediately washed away into the tank. Also, although these are sold as ‘hydroponic grow media’ what I was hoping for was LECA – lightweight expanded clay aggregate – which is frothed up with air holes and texture to retain water, but these clay spheres are smooth and solid and don’t seem to hold much moisture.
Lava rocks don’t stack and stay too wet (doesn’t work)
The next attempt was small pieces of irregularly shaped lava rock. The lava rock doesn’t just instantly roll away and can be successfully piled up. The odd piece does come lose and escape, but at least you can make a pile of lava rock in the current. The issue with these is that unlike the clay spheres, the lava rock stays really wet. I made as high a pile of these as I could without them falling over into the tank and the top of the pile was still completely saturated with water. I tried growing both Echinodorus grisebachii ‘Tropica’ and Anubias coffeefolia sitting on top of the lava rocks, but the wetness was rotting both of these plants and I suspect also drowning the roots. This was at least partially successful for a while as both the echinodorus and the anubias put out a few new leaves (before the rot set it) so at least there is some potential promise. I think the top of the plant needs to kept drier as do the upper parts of the roots for this to work.
Combining an aquarium type system with a hydroponics set-up is termed ‘aquaponics‘. Since it is the emersed plant part that has been problematic I’ve been browsing literture on how to have a successful hydroponics part. There are a number of proven techniques, none of which resemble the setup on the shelf of the Shrimphaus, naturally. I’m giving a go to passive wick-system hydroponics, where inert media, in this case the clay spheres, is kept moist by the proximity of a wick that can carry water from the base of the container to the top. The wicks used here are cut up strips of an automobile synthetic chamois cloth – this part seems to be working really well. Three wicks seem to be needed to keep the clay balls reasonably moist/damp without being altogether wet. The echinodorus and anubias look pretty sad in these pots so far, but they might rally…
The airstone does a great job of keeping the surface of Shrimphaus clear from biofilm, but how it does that exactly isn’t clear. One idea is that when the bubbles break on the surface they fling water and biofilm in random directions, including over the side of the open topped tank. For sure this flinging of water happens, whether or not biofilm goes with it. This leads to a gradual build-up of minerals on the sides of the tank above the airstone from broken bubbles after the water has evaporated. I was going to be ok with that, but it turns out the amount of water flung over the side is sufficiently substantial as to wet the wooden surface of the table supporting the Shrimphaus. Wet wood is not a good idea so this is a problem.
Try putting the airstone in the middle
I’ve moved the airstone to the middle of the tank on the bottom. In this location the bubbles spread out evenly over the surface of the water but don’t get close enough to the sides to fling out water (and biofilm), or at any rate this happens to a greatly reduced extent vs with the airstone mounted on the side wall of the tank. This arrangement of having the airstone away from the walls will be a pretty good test of whether the main mechanism by which an airstone removes biofilm is through simple mechanical disruption in which case the biofilm won’t come back, or rather by evicting biofilm from the tank by throwing it over the side. If the mechanical disruption from the centred airstone isn’t sufficient to keep the biofilm in check, the usual way of removing biofilm is with a skimmer, but that’s another piece of complicated kit to have in the tank which isn’t entirely shrimp-safe and you don’t get the benefit of additional oxygenation (as much?).
The shrimp don’t seem to have noticed or cared about the relocated airstone yet. I’ll update on the effectiveness of biofilm prevention, any residual flung-out water/mess and any emerging shrimp behavioural changes as the new set-up settles in.
Two week update: airstone in the middle is working
It’s been two weeks now since relocating the airstone to the middle/bottom of the shrimphaus and the airstone is working great. There has been no sign of biofilm formation and no more mess flung outside the tank. It seems the mechanical surface disruption is preventing biofilm formation. All together, I’m really pleased with how this worked out. I also found a piece of slate to keep the airstone in place, even though that seemed not really necessary.
shrimp on the riverbank
Particularly after a water change, the shrimp like to collect on the river run shelf. I’m not sure what they’re after here, but this is a consistent behaviour of theirs. This is the kind of thing you’re not going to be able to observe without a shallow flowing water component to your shrimp habitat – something which I suspect is pretty unusual. They also like to sit in the flow generally, but the water change seems to really get them going. Others have seem similar behaviour from their shrimp during water changes.
Do cherry shrimp leave the tank?
shrimp doing a pull-up
In my experience, the shrimp do not leave the tank and I’ve never found a dessicated shrimp on the floor. That being said, they do seem to enjoy shallow running water and from time-to-time one seems to get a little creative about exploration. Here’s an interesting video example of a bloody mary shrimp (Neocaridina davidi) lifting itself out of the water. Fortunately, they don’t do this very often and are sensible enough to get back in the water directly.