Seawater DIY

May be you too have wondered, whether it's really necessary to buy salt mixtures for saltwater tanks. Some state, they don't make any water changes in years, thus don't mix seawater. Others say you need those products for sure, since the organisms in your aquarium consume minerals and other nutrients and these must be replaced through water changes.

Well, I see their point and can't imagine either, how you could run a saltwater tank without water changes. But I'm a pathetic DIY guy, that's why I did some research about the composition of sea water. After finding the main elements and their percentage in seawater the question was: with which minerals could we get this exact mixture? 
https://en.wikipedia.org/wiki/Seawater#/media/File:Sea_salt-e-dp_hg.svg

After thorough research about the weight of atoms and molecules I composed this recipe:

267 grams of Sodium chloride (=salt)
16 grams of Calcium chloride
7 grams of Potassium chloride
34 grams of Magnesium sulfate heptahydrate (=Epsom salt)
52 grams of Magnesium chloride hexahydrate

dissolved in 10 liters of warm water. 

That's it. Of course there might be a need of particular macro and  micro nutrients, but this depends on your stocking. Anyway I would advise to add some iodide, e.g. Potassium iodide, this should be done every day, when lights are switched off, since iodide dissolves under light.

I'll post a DIY solution for micro elements soon...

New Mediterranean Sea Biotope

It's been quite a while... This is my new project:

80 litres tank
2 internal filters
3 levels of LED lighting

That's it...

As usual all inhabitants are collected in the Black or Mediterranean Sea. Start up is as a Black Sea biotope. This is because I live in Bulgaria, the Black Sea coast is just 2 hours away. Most species are interesting, hardy and can be adapted to normal salinity. There are a lot of fish in the Black Sea, easy to find and catch...

Thus I started at the end of May, 2019 with this:

Something new I tried is artificial rock made from brick, wrapped with expanding foam and covered with gravel from the sea. The reason is to have a small rock with holes and crevices where all kind of species can settle. And it worked out actually.

Later I raised salinity and collected some stuff from the Mediterranean Sea:

Now it's November and it'll have a break. I had some algae trouble while setting up, although this normally doesn't happen, since I get live sand, live rock and fresh water from the sea. But may be because of the artificial rock and high temperatures during summer we had a hard time. But it looks quite balanced now...