Who is Leonardo?

Leonardo’s Reef was founded in 2009 by Leonardo den Breejen, and gradually specialized in the propagation of corals from the Acropora genus. 

Leonardo, better known as “Leonardo’s Reef” online, has been a reefkeeper for over 20 years. In this period, he gained recognition with several projects such as “Formosa Forest” and “Apogon Reef”, has been featured on boards e.g. Reefcentral and Thereeftank, websites e.g.  Reefbuilders, and magazines e.g. Reef Hobbyist Magazine. Currently, he is the head of the Leonardo’s Reef coral farm and is a University lecturer in Biology.

The ideas behind Leonardo’s Reef

Leonardo’s Reef was founded because of three important reasons. 

  • Declining health of coral reefs in the wild
  • The large carbon footprint of imported corals
  • The amount of corals that don’t survive import and/or acclimation (long-term) 

They made us think about better ways to provide the hobbyists in Europe with a great variety of Acropora corals. Our answer to these issues is: locally aquacultured Acropora.

Local propagation of Acropora has more benefits than the ones mentioned above, most importantly:

  • Higher survival rates of the corals in customers’ tanks
  • Stable Acropora colors and growth patterns
  • 100% pest-free corals thanks to our closed systems, strict protocols and quarantaine

Our corals

Since the founding of Leonardo’s Reef,  we have avidly collected as many species, hybrids and morphs, especially Acropora. We have over 300 different species of Acropora in our collection, and it is still growing. We are passionate about this genus, from the most ordinary green Staghorn to the High-End A. speciosa, we collect them all.

We select the most interesting Acropora by hand. We browse through retail stores, wholesalers, importers and hobbyists’ tanks to pick out the most interesting gems to propagate in our systems. We aim to be a true “coral-bank” where every species and morph is available! 


To understand more about the physiology and reproduction cycle of Acropora corals, we are building an Acropora spawning laboratory which will be completed in 2023. In this new facility we will find ways to use sexual reproduction (also know as “coral spawning”) for propagation purposes, as well as hybridisation. Please visit our website Coralspawning.com soon for more information. 

Our customers

Working with corals every day is fantastic, frustrating, exciting, and sometimes heartbreaking. But most of all, we are grateful for our customers that make it possible for us to pursue the dream to be the largest aquaculture facility in Europe for the Acropora genus. 

This means we always take care of our customers, make sure that they are happy with their purchase long-term, and invest in a lasting customer relationship. If you have any questions, comments, or anything else, please contact us!

System information and parameters

Since we moved into our new facility in Almere (NL) in 2021, we have 5.000 liters of systems to propagate Acropora, with double the capacity in 2023 to at least 10.000 liters of Acropora-only aquaculture.

We use a combination of T5 and LED lighting in the form of ATI Hybrid fixtures, Ecotech Radion G6 and are experimenting with Reef Factory Reef Flares on some smaller systems. 

We keep maintenance as simple as possible. We strictly use Tropic Marin products and salts, mainly Pro Reef Salt, Full-Balling elements, A- and K+ trace elements and Iodine. ICP is done monthly by ATI. No other “methods” or additives are used.

We keep parameters as follows: we keep water parameters close to natural seawater (NSW), so the transition to our customers’ systems will most likely be minimal. Even if they don’t match exactly, it’s not a big issue. The corals can and will adapt, as they did in our husbandry for a long time. Stability is much more important.

  • Photosynthetically active radiation (PAR) levels range between 250 μmol·s−1 and 500 μmol·s−1 depending on corals species.
  • Temperature: 24,0 – 26,5 C
  • DKH : 7.7-8.3
  • Calcium : 430 – 450 ppm
  • Magnesium : 1350-1450 ppm
  • Nitrate : 1-5 ppm
  • Phosphate : 0.05-0,06 ppm
  • pH : low point above 8,1, average 8.3

How do we make our photos?

Because we care about our customer satisfaction, we want to present our corals as close to reality as possible. This means we use a combination of T5 and LED (14.000 Kelvin light temperature) to make our photos, never use any filters or heavy photo editing software. 

If you have any further questions, please contact us.