So I bought ten propagules off
amazon July 2019 to put in the sump of a 29 gallon brackish tank for which I was using to raise a baby diamond back terrapin we found almost dead on the beach when a bird dropped it. At the time the turtle was about the size of a silver dollar and i was using a small led grow light for the mangroves. I had them a small sterilite container in about 3 inches of fine sand inside the sump. I also had mollies to keep the turtle company. They bread like bunnies and every now and again squirtle the turtle would catch one.
About a year later the turtle was about 6 inches long and too big for the aquarium, so I transferred it all to a 125 gallon tank with a larger sump in the cabinet underneath. By this time the propagules had 4 - 6 leaves each and had grown very little. I kept them in the same little sterilite container with 3 inches of sand inside the new sump. I also slowly raised the specific gravity of the tank from 1.010 to 1.023 over a few weeks so that I could give have a full marine tank. I added some hermits, snails and marine fish to the new tank over time. The mollies continued to thrive at full marine salinity.
About a year ago the mangroves had outgrown the cabinet space under the aquarium (about 16 inches tall) but were still growing at a snails pace, so I did something crazy. I got a huge plastic pot and filled it with aragonite ( 2 feet deep of sand!) then plumbed it to the aquariums sump with a slow flow.. and put all that inside a grow tent with a more powerful led grow light, then replanted the mangroves completely into the pot discarding the old sterilite container. This is where things got interesting!
Within days the big pot filled with a think green algae coating with all the new lighting going on. I put some nerite snails, cerith snails and blue leg hermits in the pot and they quickly cleaned things up... and within a few weeks one of the mangrove trees just took off like a weed (I'll name this mangrove Boss for reference), several kept growing snails pace... and about half flat out rotted and died! Pretty sure the mangrove deaths can be attributed to the root damage that occurred transplanting them to the big pot. Under the sand was a huge network of super fine and fragile hair like roots that were near impossible not to tear up during transplanting.
About 2 months ago Boss did something amazing! He sprouted 3 prop roots! Within 2 weeks the sprouted prop roots made touchdown to the sand like a tripod! They grew out FAST! Now within just the last week four more prop roots have sprouted further up the trunk of boss! I'm having to trim boss now to keep him from outgrowing the tent, and he grows so fast that you can see it from one day to the next. Definitely doing a lot of nutrient exporting now. Better than chaeto at this point for sure. But it took YEARS and a big pot to get to that point. I've attached pictures I just took today. Notice how skinny the non-boss mangroves are?! Notice some of the new prop root sprouts on boss? I've always read you have to suspend the propagules to get prop roots, but not true. It took years, but all of the sudden I'm getting prop roots growing at lightning speed.
