Today I shifted the location of the CO2 diffuser from the left wall of the tank to behind the moutain and underneath the powerhead.  The atomised CO2 gets sucked up directly into the flow and actively pushed around the tank.  Previously I had the diffuser on the opposite side of the tank hidden under the plants and whilst it seems sensible to put the CO2 where the plants are, because the flow pattern is circular, that puts the plants “upstream” of the diffuser last in the queue – the water has to do a full circuit to get back to them and by that time all the microbubbles have already reached the surface.  Those plants can still benefit from the dissolved CO2 of course, but they won’t get any microbubbles trapped under their leaves.  The diffuser is also now hidden behind the mountain, which is good, and is shaded by the powerhead to reduce algae growth on the diffuser, also good.

While I was moving things around and doing a cleanout I also took the opportunity to clean the diffuser by removing it from the tank while still active, layering on a few drops of liquid carbon, and letting that go for 10 minutes or so.  Back in the tank this increased the CO2 flow rate from 120 bubbles per minute to 130 bubbles per minute, so that worked well.

The fish seemed pretty happy about the whole thing but it will take a few weeks to get an opinion from the plants and algae.

Notes:  Cute video of a 5-banded barb swimming through the tunnel under the mountain.  The plant growing on the mountain is Bucephalandra caterina.  The carpeting plant at the base of the mountain is Marsilea hirsuta.

After spending some time thinking about how to deal with the  top-heavy mature form of Lobelia cardinalis ‘Wavy’ even after a very aggresive trimming, I decided to pull it out and replace it with a (hopefully) smaller form:  Lobelia cardinalis ‘Dwarf’.  There are still challenges with aquatic plant supplies so when I got notified by Aqua Essentials these were back in stock I picked up two pots straight away.

These dwarf lobelias are grown in emersed form in rockwool by AquaFleur in the Netherlands.  When they arrived they were larger than I had expected and carefully prising away the rockwool with pinsettes revealed three good-sized individual plants per pot.  You’re never entirely sure how many individual plants will come in each rockwool pot –  the catalogs tend not to list this information – sometimes it’s one plant per pot, and other times a good many.

The pinsettes made planting easy.  There’s a perspective shift when looking through the aquarium acrylic walls at an angle and although I thought I was planting these towards the front, the side-on view showed they are actually about halfway back, which is fine.  The Lobelia cardinalis ‘Wavy’ adapted to submerged-form growth almost immediately, so I’m optimistic the dwarf form will as well.

The fish were very interested in checking out the new situation…

Nothing has really dramatically changed in the Fireplace Aquarium but I feel the green spot algae has been growing back quicker than it used to.  I was having to give the tank walls a credit-card scrapedown every three or four weeks, but now it seems up to every other week.  I tried increasing the dose of liquid carbon (a.k.a algaecide) from 1.0 ml per day to 1.5 ml per day, without noticeable effect other than using up 50% more EasyCarbo.  For sure though the hours of daylight are increasing rapidly now and even though the aquarium is 4m from the window, it is a south-facing window and bright all day long.  I’ve reduced the lighting supplied by the Tuna Sun LED light by reducing the period of full intensity light in the aquarium daily lighting sequence by 2 hours per day, so we’ll see if that helps.  I have long suspected that I’ve been providing more light than necessary so let’s give this a go.  I’m also going to knock the liquid carbon dosing back down to the original 1.0 ml per day.

Continue reading “Green spot algae in the summer”

Managing CO2 flow rate satisfactorily is particularly difficult for smaller aquariums; it’s very easy to have the CO2 come blasting out, but a nice steady well-controlled bubbling takes some work.  The usual combination of regulator and needle valve can work, and adding in a secondary flow restrictor between the two can be a big help.

Mott porous metal flow restrictors

Mott porous metal flow restrictor
Mott porous metal flow restrictor

Plastic flow restrictors that work “well enough” can be had for as little as £5, but I’ve always been enamoured of the porous metal flow restrictors from Mott corporation.  A metal disc has hundreds of microchannels fabricated into it such that the gas has to squeeze through to the other side.  By controlling the size and number of the channels and the shape of the disc, any desired flow rate can be achieved for a defined gas supplied at a defined pressure.  I managed to score the pictured one from Ebay.

Fireplace Aquarium Mott flow restrictor

Mott calibrates the flow rate against nitrogen gas with an input pressure of 30 PSI which is a typical regulated gas output working pressure.  The one I got is calibrated to 10 SCCM (standard cubic centimetres per minute) which is to say, 10 ml.  CO2 is less viscous than nitrogen, so this restrictor outputs a flow of 12 ml / minute CO2.  I find that for the 8 hours per day the CO2 is flowing through the aquarium (controlled by a solenoid on a timer) I need a flow rate of 6 ml / minute CO2, or maybe slightly less, so this is the perfect flow restrictor for this set-up.  Given an input flow rate of 12 ml / minute CO2 the needle valve has no trouble at all comfortably getting the flow rate down by the remaining 50% needed.  With the new restrictor in place adjusting the needle value smoothly moves the flow rate up and down, with none of the twitchiness exhibited with much higher input flow rates.

Continue reading “Managing CO2 pressure”

Force-directed directory structure of
Screaming Frog site visualisation

On the recent discussion of seach engine optimisation using the Screaming Frog web-spider tool there were some visual representations of the structure of the Fireplace Aquarium site.  These do a nice job of illustrating the higher-level structure, but don’t convey a good sense of the internal connectivity of the various pages.  Browsing the interwebs on the topic I came across an interesting implementation by Kiran Tomlinson, done while a PhD student in Computer Science at Cornell.

Below is a view of the Fireplace Aquarium site generated using Kiran’s app that shows the direct linkages between resources.  Pages are blue spots, images or any other internal non-page resources are green spots, and anything external is shown as a red spot.  The graph is zoomable and slideable and you can hover over the individual nodes to show which resource they represent and highlight direct connections to other resources.  Try click-dragging any one of the nodes to see what happens.

Fireplace Aquarium connectivity graph (25-Mar-2021)

As you might expect for a WordPress site, there is a central ball of very highly interconnected resources.

Time lapse  sequence following major aquarium plant trim

About a month ago I revised the layout of some of the aquarium plants.  I didn’t like the look of all the stemmy/rooty bits of the Lobelia showing up against the front wall of the aquarium so I planted a row of dwarf Cryptocorynes in front to grow into a low cover.  The problem though was the lobelia were already crowded against the front.  When one of the lobelia plants came loose it was an opportunity for a do-over and I removed all the lobelia except the smallest plant closest to the left side and replanted lobelia trimmings taken from the removed mature plants in a line a bit farther back from the front wall.  Some of the ludwigia was also looking a little ratty with heavy algae cover on some of the lower leaves so I did a pretty aggressive takedown there as well.

Continue reading “Aquarium plants recover from trimming”

Planting Bucephalandra caterina

Bucephalandra caterina pots
Bucephalandra caterina pots

Looking for a replacement epiphyte for the failed Anubias nana ‘Snow White’, I’ve plumped for Bucephalandra caterina.  There just isn’t much availability for aquatic plants in general in the United Kingdom recently, and the availability of Anubias and Bucephalandra varieties seems extraordinarily poor especially for the smaller size varietals.  I managed to score two pots from Pro Shrimp, as grown by Aquadip, and they arrived today.

Species and varietal names are not very well defined for Bucephalandra with several hundred types known (or claimed).  There’s some question as to whether Bucephalandra caterina is (or is not) the same thing as Bucephalandra ‘Mini Needle Leaf’.

Bucephalandra caterina pots are each their own individual plants

Bucephalandra caterina pot with rockwool removed
Individual plant (right)
Bucephalandra caterina pot with rockwool removed
Individual plant (left)

I was expecting each pot to be composed of a number of plantlets that could be easily teased apart and planted separately, like the Cryptocoryne lutea ‘Hobbit’, but this was not the case.  Once the rockwool was removed from the roots it was clear that each pot was its own defined thing that was not obviously subdividable.  I suppose I should have expected that from a plant that grows from a rhizome, but I was thinking of the Anubias nana ‘Snow White’ tissue culture pot where there were many individual plantlets even though Anubias also grows from a rhizome – that might be a difference between growth in pots vs. in tissue culture.  I thought about cutting the Bucephalandra in half with sharp scissors, particularly the one on the left that sort of looked like it had a semi-obvious point where it could be divided, but in the end decided to plant them ‘as is’.

Continue reading “Planting Bucephalandra”

Easy SEO anyone can do

Did you arrive at the Fireplace Aquarium by way of a search engine like google or bing?  How search engines choose which sites to show and in which order can be influenced by ‘search engine optimisation’ or SEO.  An important aspect of SEO, in addition to having interesting and informative content, is having the technical aspects of a website sorted out such that the website facilitates the content instead of getting in the way.  Currently, I’m working on the following pieces:

  1. No broken links, missing pages or ‘404’ errors or other obvious sources of user frustration
  2. Informative meta descriptions for web pages so search engines don’t have to guess what to say
  3. All images have an ‘ALT’ text description to aid the visually impaired and help search engines understand the messages images are conveying
  4. Verifying that search engines know about all the different pages they might decide to index using Google Search Console (or similar)
  5. Add headings that match questions Google searchers have asked* and provide helpful answers to those questions.
Screaming Frog SEO spider logo
SEO spider

How to use Screaming Frog for SEO

A really great tool to help accomplish the above is the Screaming Frog SEO spider.  You download and run the app**, then point it at your website where it then ‘crawls’ all the interconnected pages exactly like the search engines do, collecting information you can query in a user-friendly way.  For example, you can click a button to see a list of all the broken links in your website (or ideally, see that there aren’t any broken links).  Similarly you can query which pages have meta descriptions, which images have ALT descriptions, and what those descriptions say.  It’s also easy to generate a list of all the web pages, and indications as to which can be indexed by search engines, and then to compare that list with pages actually indexed by google or bing etc.  Where the search engines have missed some pages, you can point the engines to those pages specifically.

How to make a Screaming Frog sitemap

One of the cool things you can do is to generate visual sitemaps, either based on the directory structure, or the route in which the SEO spider crawls the site, and see those as either a tree graph or force-directed graph.  The graphs can be exported in either SVG or HTML format; unfortunately, WordPress doesn’t play well with SVG, so I converted the SVG saved output to PNG using Gimp and you can see two versions of the results below. structural visualisation 11-Mar-2021
Directory tree graph
Force-directed directory structure of
Force-directed graph

Making the sitemap is easy.  Launch up Screaming Frog and type the base address of the website into the ‘Enter URL to spider’ address bar at the top, press ‘Start’ and wait for the scan to complete.  Then select your visualisation of choice from the Visualisations menu.  Once the visualisation comes up, have a play with the settings by clicking on the small gear icon in upper right corner of the visualisation window.  When it’s looking how you want it to, click the diskette icon to the immediate left of the gear icon to bring up the save screen, pick where you want the visualisation to be saved, select either ‘svg’ or ‘html’ format from the dropdown menu at the bottom right of the save screen, and then press ‘Save’.

*Real world example:  I clicked the ‘Performance’ tab in my Google Search Console and found I was getting queries for “screaming frog visual sitemap”.  I then did a google search for “screaming frog visual sitemap” to see what people wanted, and the search result page helpfully said:

People also ask:

  • How do I make a screaming frog sitemap?
  • How do you use a screaming frog for SEO?  [really, that’s what they ask]

So I made level 2 headings corresponding to those two questions, and then (hopefully) provided some helpful answers.  If you found these answers were helpful, you could thank me by linking to my site from your website, ideally with a “do follow” link. 😀

**Screaming Frog is a UK-based outfit (which is nice) and provides their SEO spider free of charge for use with smaller websites (less than 500 URLs).  They claim versions for Windows, macOS and Ubuntu, however, I develop Fireplace Aquarium on a Chromebook running Debian linux (the testing repository) and much to my surprise (and delight), the Ubuntu .deb file installed using gdebi without incident and seems to run just fine under Debian. ➔ favicon

Today I changed the domain name for the Fireplace Aquarium from to niade.comDreamhost (my web hosting provider since 2005!) made the WordPress domain changeover process super easy:  register and host the new domain name, go into the web hosting control panel, push the appropriate button and in a minute or two everything is switched over.

What to do with the old domain?

It’s poor form to deactivate the old domain and let anything out there with links or bookmarks pointing to the previous site break with 404 errors, so I’ve instructed the old web pages to automatically redirect to the corresponding new versions.  Naturally, Dreamhost made the redirect process super easy as well.  (Check it!


Hylas and the Nymphs by J.W. Waterhouse
Hylas and the Nymphs

From time to time I have a poke around at what might be available in short and usable domain names, ideally with the .com TLD.  The usual result of this exercise is “not much”, but in this instance was available and since it reminds me of ‘Naiad‘ – freshwater nymph – it has a vague watery/fishy feel to it that seemed appropriate.

Web browser fish icon

The ‘favicon’ is a small 16 x 16 px graphic you can see before the web page title in each tab of your web browser.  The favicon is an homage to the 5-banded barb (Puntius pentazona).

It’s been six weeks since the Cryptocoryne lutea ‘Hobbit’ was planted so it’s time to take a look at how the emersed growth form from the shop compares to the submerged growth form in the tank.

Aquarium plants for commercial sale are, for economic reasons, almost exclusively grown “emersed” – the roots of the plant and whatever media they are planted in is kept submerged underwater in the nursery but the leafy part of the plant is grown in the open air.  There is a massive difference to the plant, however, in growing with leaves in the open air vs. leaves that are always submerged underwater, and so plants will very often have a different form of leaf, sometimes dramatically different, after they get established in the aquarium.  You can see the effect in the Fireplace Aquarium with e.g. ludwigia and lobelia and now here we see it with the Cryptocoryne lutea ‘Hobbit’.

Continue reading “Cryptocoryne lutea ‘Hobbit’ – submerged vs. emersed growth”