So, lets take a look at some less than successful things that happened in the first year of the Seagrass Sandbar Lagoon. I can think of two that stand out. I'm sure there were more, but my mind is good at forgetting my goof-ups.
First, I never got my water movement situation to the point that I wanted. I wasn't able to get my main circulation pump up and running, because I wasn't able to get enough flow through the out-flow part of the closed loop. This caused multiple issues, not the least of which was a huge amount of micro bubbles. I attempted several solutions, like the 'question mark' stand pipe, to no avail. I thought of some other possible solutions, but they required me draining the tank, and I don't have the tools I'd need to do them. I also realized that my pump was too loud to do the job in my living room. Combined, these issues caused me to take a pause and consider my alternatives. I am now researching pumps that are quiet and adjustable, to meet my needs. In the meantime, my tank has a lazy, back and forth flow from the wave box and additional circulation through my canister filter. It's not ideal, but it's not a disaster. Seagrass lagoons can be pretty calm. And the back and forth wave action does an excellent job of mimicking Nature.
Number two was kind of a biggie, and one I have a hard time forgiving myself for. Just as my manatee grass was taking off, reproducing like crazy, I noticed some were turning yellow. I was slow to react, given the great growth, but that hesitation cost me dearly. Over the course of a couple months or so, I went from around sixty plants to around thirteen. Yep, the plants I care the most about were almost wiped out, because I didn't react quickly enough to their decline. Yikes, what a screw up! In my defense, manatee grass is tricky, because of it's relatively slow growth, it's hard to know what is affecting it. So you try something to benefit it, and then you wait for a couple weeks to see results. So it's difficult to know if what you're doing is working, or is some other unknown factor affecting them.
Luckily, I noticed the decline looked a lot like the decline I saw in v1, when I reduced the salinity to hypo levels. I checked salinity, and sure enough it had dropped significantly. I traced the drop to my feeding regime. I was putting frozen food in fresh, RO/DI water, so I was adding fresh water three times a day. I have since switched to using tank water to thaw frozen food. I'm also more vigilant in checking the salinity level.
One silver lining to this calamity was the uptick in growth of my shoal grass. It liked the drop in salinity. So, while my manatee grass was disappearing, the shoal grass flourished and really filled in the empty spots nicely. In fact, I ended up with a surplus that I am now in the gradual process of pruning back.
In the months since, the manatee grass has bounced back pretty well. I have been able to transplant several to get them better distributed. I have more to transplant this winter, before the spring growing season, but overall, I'm in good shape to have a good patch of manatee grass by summer.