[johnwesley0]

I've been experimenting with a ten gallon Chinese porcelain bowl as a suitable aquarium over the years. I'd had pretty good success using a Fluval cannister set up and a couple of sprigs of anubias barteri The bowl gets about an hour of direct sunlight a day. Things were fine until I started experiencing a series of nitrogen cycle crashes long before I properly understood what cycling actually meant. But, since Jan 4, 21 I've had terrific results using nothing more than a container of old bio media from the old setup and the addition of about 4 lucky bamboo plants (a fifth got water-logged and died.) Just gravel substrate; the curved walls of the bowl direct all fish waste to its center where there is now a thin layer of mulm. The parameters have been stable for nearly six weeks: 0 ammonia, 0 nitrites, 15-20 ppm nitrates. Not quite sure how to attach a photo, but I like the conservatory look it lends to my Brooklyn flat. The only Con is that the silica in the porcelain tends to attract diatoms.

 

[johnwesley0]

So, one question came up on another fish forum concerning the role of beneficial bacteria (BB) in the water column. The other forum which can safely be characterized as a Nitrogen Cycle hub, the insistence is that BB only exist on things : the bio-media, substrate, decorations, etc. And, that the water column has to be filtered through it. But, I question that since I've had no filtration for almost two months and cycled fairly quickly (two weeks) with nothing more than 7 gallons of standing water and five zebra danios. Oh, and four lucky bamboo plants. Is it possible for lucky bamboo to convert that much ammonia that quickly or can "floating" bacteria contribute its share to the nitrification process?

 

[johnwesley0]

You can see floating bacteria if your water is cloudy, otherwise, they're on surfaces most times.
Yes, plants love ammonia.

Thank you, that makes complete sense. Of course, water would have to be pretty nasty looking to have that much bacteria floating around. :smile: As for plants and ammonia, it now becomes clear why I was able to go for months and months without ever changing water when I was a youngster and why everyone on the other fish forum is obsessed with it. When I was young, all of my tanks were heavily planted. You could buy cobomba, vallisneria, and sagittaria pretty easily and every fish book recommended them - but, never because of their role in the nitrogen cycle. It was because you were afraid your fish would suffocate for lack of oxygen. I think I gradually got away from plants as my obsession with filtration grew over the years. Glad to be back to the natural world!

 

[johnwesley0]

You can see the old bio-media cartridge at 9 o'clock. I can probably toss it, right?

 

[johnwesley0]

Just tested the parameters again and there's been very little change: 0 ammonia 0 nitrites and 20 ppm nitrates. It's been three weeks since the last water change.

 

[johnwesley0]

Just tested the parameters again and have noted a nitrate level that appears to be bumping up against the 40-80 ppm level. That's after 5 weeks without a water change. So, some water change appears to be in order.

Likewise, there had been some concern about the ph creeping up in alkalinity since the beginning of the month. Today it measured 753 on my LED pen. As I've mentioned in other threads, I live in Brooklyn and I'm not accustomed to having alkaline water. So, I've removed my ancient and revered sea shell rock pending the water change. By the way, is fish poop acidic or alkaline? I forget. Perhaps, a good gravel rinse is in order, too?

All in all, I'm delighted with how things are coming along. If anyone had told me I could maintain a tank with five fish and no mechanical filtration for over two months l would have not have believed them.

Btw, that smudge at 9:00 is where the rock used to be. I can't decide whether that is leftover diatom or bacteria? I thought I would leave it for now.

 

[johnwesley0]

The glass cover habit is one that I picked up while growing up in Jamaica, NY where the water supply is completely separate from the rest of New York City and was notoriously hard and brackish. Thus, I lived in fear that evaporation made the water column more salty. So, just how much do I have to worry about adding water to top off evaporation generally?

 

[johnwesley0]

All of my tanks are open top and my tap water is hard. I top up the tanks whenever they need it, and do a large water change three or four times a year.

Thanks, Michael. I actually prefer the bowl open. The open pool look is why I chose to go porcelain in the first place!

 

[johnwesley0]

Goldfish were kept in large porcelain bowls in ancient China. Goldfish & koi were bred to look good from the top view.

I've had reasonably good luck with both in this bowl. At some point, however, they both will benefit from being in a larger tank (at least 20gal.) And, the poop level might be a little too much for a walstad tank; the koi definitely needed a cannister filter.

 

[johnwesley0]

So...it's been 3 months since the beginning of this set-up and I am over the moon by the results so far. No filter. No artificial light. Stable parameters. I've gradually added six glo-fish danios that easily present as tiny goldfish when viewed from above and they couldn't be happier. I've just completed a 20% water change after 3 weeks and the nitrate level appears to have been reduced from ~40 ppm to between 10-20 ppm.

One of the more interesting recent developments is the ongoing battle between the duckweed/wolffia and the beneficial bacteria that is slowly making a return to lower left-hand side of the bowl. They seem to take turns waxing and waning, depending on conditions above the water line. The duckweed appears not to like condensation and has visibly melted since I started covering the bowl again with a glass top. The lucky bamboo seemed okay with it. As an experiment, I'm going to start leaving the bowl uncovered again.

 

[johnwesley0]

Fascinating update on the wolffia vs. beneficial bacteria (BB) battle. I left the bowl unattended for 10 days while I took a holiday away from the city (I've been fully vaccinated.) When I returned, I realized to my horror that I had not correctly turned on the automatic feeder. My six danios were perfectly fine, but they had effectively resolved my wolffia problem. Their disdain for vegetables which had been evident when it was first introduced about six weeks ago was quickly set aside when no other food source was available.

Not coincidentally, IMO, the beneficial bacteria has taken over one side of the bowl. I have now been a member of the APC community for two months and I'm rather jealous of the focus on exotic plants. One of these days I'd like to start a dirted tank. But, in the meantime, I wonder whether there is some way I can adjust things in my low-light, low-tech porcelain bowl so that plants (any plants) are more competitive with the BB for nutrients? I'd like to make it completely filterless but I'm beginning to realize that part of the problem is that porcelain seems to be a BB magnet.

I'll add a snapshot when the sun gets a little higher, later in the day.

 

[johnwesley0]

Haha! Finally got some dirt in my bowl. It feels good. The pot contains a white lily bulb (nymphaea.) It's already sprouted some stems. The water may be too deep for it at this point so I may put the miniature milk crate back in and lift it up a little. Also, the pet store owner sold me on giving the floating plants another shot. He says, this isn't duckweed but I'm not going to split hairs:

 

[johnwesley0]

I spent most of yesterday worrying whether the packing media the lily bulb/rhizome came in was peat moss because it never occurred to me to switch it to a different substrate. My tap water is already pretty soft and I know from experience that filtration tends to lower ph over the long run. So, I got up this morning perfectly prepared to replant the lily when upon close examination, I realized its tiny leaves are already unfolding:

Guess I'll leave well enough alone?

 

[johnwesley0]

I'm starting to see why people enjoy dirted tanks so much. Dirt adds a whole other dimension to the hobby. So, this morning's mission was to order the API KH/GH test kit. I've been guessing at my water's hardness and alkalinity by proxy for too long and I'm beginning to realize that I have a growing adolescent lily in my bowl. Guessing may no longer be good enough. So, back went the seashell rock which was also prompted by a sudden drop in PH from ~730 to 703.

I think the peat in the lily pot may be the culprit here. I lifted the entire pot out of the water in order to tuck in some root tabs. I actually did it several times and the result was that with each lifting, the tannins dripped from the bottom of the pot like a perking coffee maker.

The tannins will clear up, I'm sure. I'm not worried about it. But helping those lily leaves to reach the surface of the water is now my chief goal.

 

[johnwesley0]

Got it. Hoping that with regular 20% water changes every few weeks it will dissipate. Trying hard not to let the discoloration make me crazy. Also, hoping that once the lily looks healthy and strong, I can just re-pot it. Here's the little darling on Day 3 in her new home (I've already decided she's a girl.)

 

[johnwesley0]

Been playing with the water hardness test kit since it arrived shortly after lunch. It confirms what I already intuited, that my water is very soft, probably too soft for the most exotic aquarium plants. It also explains why the neighborhood pet stores carry such a small selection (annubias, and lucky bamboo, as it happens, being among the most popular.)

My KH is about the same in bowl water and tap - 3-4 dKH

But, my GH is almost 5x greater in the bowl than right out of the faucet 1 dGH versus 5 dGH.

The recent addition of some peat and re-addition of the sea shell rock to the bowl are confounding factors. The PH seems to have stabilized at 7.03. It took the rock a few weeks to pull the PH up to 7.5 before I got nervous. Perhaps, I should just let it do its thing before I do anything more drastic (like repotting the lily into some Miracle Gro?)

 

[johnwesley0]

Oh, it's the peat moss that came with the packaging. That's one of the confounding factors.

 

[johnwesley0]

What's in the pot? Just gravel?

Just gravel.

 

[johnwesley0]

Oh, the lily will live off the bulb but after a while it’ll need nutrients.

That sounds reasonable. In the meantime, I'll keep an eye on the KH level. If the sea shell rock isn't raising it sufficiently by the time the lily reaches 6 inches (the approximate distance to the surface) I'll consider adding some crushed coral or something. I have the salvinia to think about too.

 

[johnwesley0]

Today marks Lily's first week in her new home. So, like any proud parent I'm sharing a photo:

The PH is still dropping, I assume because of the peat moss packed around Lily's bottom. The dKH is 6; the dGH is stuck at 4. And, even though I know the water hardness and alkalinity are more important, it's the dropping PH - 6.9 - that is making me nervous; it was 7.3 just a week ago.