It’s been a turbulent month in the rockpool tank. Rising temperatures have left the flatfish looking thoroughly unimpressed, the ever-growing shore crab has followed his predecessors in being escorted back to his original pool, and the brown shrimp were pulled out just in time and tucked safely into a breeding net to avoid becoming snacks.
Meanwhile, our original and favourite blenny was taken ill, prompting emergency treatment and a temporary move to a hospital tank. Summer in the rockpool tank? More like damage control with saltwater.
Shrimp Taken Off the Menu
So yeah, as you will have gathered there has been a lot going on in the tank recently. I’ll start with the latest Brown Shrimp debacle,
I’ve had them in the tank before but it did not go well. They were fairly small, but not tiny and I thought they’d be ok. After all, I’ve got Common Prawns of a similar size in there and they have thrived. They haven’t grown, but they’ve been in there living happily alongside the bennies, gobies, anenomes, crabs etc for four months or so now.
The Brown Shrimp though? They’re basically just seen as food by everything. Even the little gobies had a go. But these particular Brown Shrimp were bigger (two and a half inches maybe) and looked like they could handle it. I learned the hard way to feed the tank first before introducing Brown Shrimp, and I also kept them in a breeding net for a week before putting them in the main tank.
At first everything was good. They buried themselves in the substrate, occasionally coming out to swim around, unbothered. Then after a few hours, out of nowhere a Blenny just went for one of them, viciously attacking it. A small Common Goby (smaller than the shrimp) then had a go too.
So I quickly scooped out the four shrimps, put them back in the breeding net where they were safe, let them eat like kings for a bit and then a couple of weeks later when I next went to New Brighton I put them back in the Mersey from whence they came. No more Brown Shrimp, not even if they’re massive ones.
A shame because they are interesting to watch and it’s cool watching how they bury themselves.
Crabzilla Gets Evicted (Again)
On that trip to New Brighton I also had to return the last remaining Common Shorecrab I had in the tank. At least I thought it was the last one, turns out there was another, a little fella who showed up out of nowhere the next day. I have no idea how that one got in the tank, but it should be fine for a month or so until it grows too big and it too will have to go back.
This is probably the fourth or fifth one I’ve returned now. The crabs are great when they’re small, but when they reach a certain size they become a problem as they’re just too unruly and are constantly causing aggro. This one has been in the tank since he was tiny though and I’d grown quite attached to him. He’s had several ‘sheds’ and usually disappears for a week afterwards, before suddenly emerging from the rocks all grocked up and twice the size that he was before.
After this last shed he became a problem as he was bouncing around the tank like the Wealdstone Raider, nipping at anything that came into his range and generally being trouble. So reluctantly I took him back to the shore. Crabs really do well in this tank environment and seem very happy, but they make life unpleasant for everything around them, even the anemones. This guy was always picking at them trying to steal food off them (not always successfully, as you can see in the video at the top of the page!).
Anyway, I put him back in a nice rockpool and hopefully he’ll survive out there in the big bad world.
Blenny in the Sick Bay
Finally, Ronnie, our favourite Blenny. We’ve had him for around three or four months now, he was the first fish I took back to the tank and I caught him in New Brighton. He’s double the size now from when we got him and he’s basically the King of the tank. He even has his own throne. The highest point in the tank is a rock in the middle, and he often just lies up there looking down on everything else. When food goes in, Ronnie eats first.
For a while now though he’s been scratching himself on rocks, and it developed into swelling. I showed photos of him to my local fish store and they said its probably parasites and to give him a bath in RO water. I did, and for a day or so he seemed better, before it got worse.
I went back, and they said its a bacterial infection and before trying any medication to give him some garlic with his food. I did, and again, for a day or so it seemed to perk him up. But he got worse, so I hospitalised him in a plastic tub with an air stone and ordered some medication online.
After five days in quarantine he was looking great and I returned him to the main tank. Hopefully that’s him out of the woods now but he’ll need to be monitored in case the infection hasn’t completely shifted.
Flatfish Are Not Into This Heatwave!
Now the only problem is the bloody heat. This hot weather we’re having is great for us humans, but not great for the tank. The temperature in there tonight at 10pm was 27.6 degrees!! I don’t have a chiller as the majority of rockpool critters don’t need it as they’re used to fluctuating temperatures in the pools they live in. The flatties don’t like it one bit though. While baby flatfish can be found in sandy pools, generally once they get big enough they go out to sea, so they are used to cooler water. The water in there tonight was so hot that even Nemo would be sweating like a whore in church.
When it gets too hot the flatfish seem agitated and will just swim up and down, occasionally gasping at the surface. I’ve got a dozen bottles of frozen water I put in when it gets too warm. It helps, but it’s only a temporary fix as they melt very quickly and its impossible to keep the temperature down for long as I have to then wait for the bottles to re-freeze. The sooner the British Summer remembers it’s the British Summer the better.
