Running A Coral Science Experiment on a Tropical Island

Added: 2026-05-05

[00:00:00]Hey everyone, it's Hadley from Sydney Reefing. As a lot of you guys know, I've been traveling around Indonesia and Malaysia trying to help set up some experiments that we got going on with the university. As a lot of you guys are interested in this stuff, I thought I'd give you guys a quick tour of the system we've got here in Indonesia and yeah, show you what I've been up to. Okay, guys. So, sorry about the noise in here.

[00:00:20]It's quite a bit loud, so hopefully you can hear me all right. I've only got one microphone with me as I've had to travel pretty light on this trip. So, as a lot of you guys know, I've been away for the past few weeks in Indonesia and then Malaysia and then back in Indonesia. Um, we've been busy setting up some experimental systems with our collaborators, Coral Catch. And there's Senna over there in the corner. She's been great at getting these systems up and running. And so, basically what we're doing here is we're actually we've come up with a kind of supplement that we can give to corals during periods of thermal stress. And the idea is that this supplement will help to alleviate some of the symptoms we see when corals are exposed to those higher temperatures. So things such as bleaching and mortality, but there's a lot of science that has to go on the background. So there's a whole other story to that. Um there's been a lot of other collaborators with the university that I'm involved with with UTS and then people over in Monaco. So this is kind of kind of the final stages of testing that. So we've tested it in Sydney and now we got to test it over in Malaysia and Indonesia under different set of environmental conditions and nutrient um things and also to so this is an ex situ experiment. So we after this one basically we want to test that the supplement works first and then we'll begin trials in situ. So trying to come up with methods of dosing the supplement there but a lot of you guys are more probably more interested in the aquarium setup here. Um it's the first time I've ever well we've ever had to set up sort of this sort of system in somewhere other than Australia. So there's lots of challenges that come with that. Um mainly lots of electrical issues but that's all sorted. So I'll give you guys a quick rundown of these systems. So basically we've got 12 flow through tanks. Each tank is kind of it's really quite similar to what you'd have at home with your home aquarium. So, we've got the top tank where we've got sort of a wave maker. Um, we've got a rack where all our corals are on. We've got sea torch lights hanging above. Um, they're giving about 200 250 PAR. I need to double check. Then we've got down the bottom, we've got the sump area. So, we've got some skimmers, we got some big titanium heaters, we've got a filter, and then we've also got some flow through. So, we can basically turn this valve here and water gets dumped right into the tank. and then it flows out through that drain at the back. So that's how we do water changes cuz when we dose these supplements, we're going to get a really large buildup of nutrients in the tanks. So we need ways that we can quickly flush out those nutrients. So that's kind of a basic rundown of the tanks [clears throat] and we've got a lot of them. So we've got 12. Um one of the biggest issues we've had here is just the amount of electricity we're using and being on a small island in Gilly Air. um the the power supplies can not be very reliable at times. Um so we've had a few issues with that. We had electricity going through these tanks and just because of the size of the heaters as well, the big 600 W heaters, um they tend to chew through a lot of electricity. So the electricians here have been doing a great job at putting it all on different circuits and everything. This whole lab used to actually be a kitchen. Um so they've done a great job at converting that into this aquarium. So, we've also had to try and build our own kind of lab here as well. Um, so if we walk in here, we've got a big bench and then we've got all our sort of lab equipment. We've got microscope way scales, magnetic stirrers for pets. Then we've got all our supplements and everything over there that we need with this system. I'll put up some B-roll footage here, but this is actually a system that we use to basically measure the health of the corals. So they're called Peter R incubations and basically we can turn the light on. We take an oxygen measurement within special chambers. We can calculate how much oxygen is in it.

[00:04:19]Then we leave the lights on for half an hour with the chamber enclosed. Then we take another measurement and we can basically calculate how much oxygen the coral has produced and that's through photo synthesis. So when corals have healthy amounts of symbiots, they generally produce more um amount more oxygen than what they consume. And we can test this by then turning out the lights and then calculating how much the ox the how much oxygen the corals consume at night as well. So this is a really good kind of fieldfriendly way of us to determine the health of the corals. We've got other ways as well such as um uh we can do photosynthesis measurements. So we've got panorometers and we can test all the health of all the corals in here. Um and then we've also got color watch charts. So, we basically put this specialized little uh color chart in the water. We take a photo. We adjust the white balance and then based on the color changes over time, we can determine whether or not these corals are bleaching. And then obviously the last one is a really simple and easy one for us. It's basically just mortality. So, as a lot of you guys know, corals who go through periods of thermal stress um tend to bleach and then if they can't get those symbiants back, they tend to die after.

[00:05:32]So that's a really good way and a quick and easy way for us to determine whether or not the supplement has helped. So if we see less mortality over time, um then we know that it is working. Um but so we're actually set back a fair way from the beach here. I'll show you cuz we've had to work out a way how to get the salt water from the ocean up into the lab. So the ocean is all the way down there. Thankfully, the water's pretty clean down there. But basically, we've got a hose running down the back of the shop here, and it comes all the way out here to the back.

[00:06:15]And the team here has done a great job cuz we've got 10 or two 5,000 L drums sitting just in here. And so, the water comes all the way up from the front of the beach up to here. And then we've got some circulation pumps going on.

[00:06:34]You can see down in there.

[00:06:37]So that holds enough water for about a week. Um the rate we're going through it. Um so whenever the tire's high and the water's looking nice and clear, we collect more water, comes up to here, circulates, and then whenever we need it, we just turn on the taps in the room there. And then we got free flowing water.

[00:06:56]But I'll go back in cuz it's it is really hot out here, too.

[00:07:00]So another consideration we've had to make with this supplement is obviously corals are very different in how they take up these nutrients and also how they're affected by thermal stress and all these things. So we're predominantly focusing on SPS here um just because uh the LPS tend to be a little bit more flexible in regards to if they bleach out they can switch to heterotrophy and they don't seem to be as affected by coral bleaching. Um, and also too, we're more worried about SPS because there's a lot of benefits that come with SPS corals. Um, especially in communities like this. They help offer a lot of protection from coastal erosion, from cyclones, and all that jazz. So, I'll show you some of the corals we've got.

[00:07:42]So, we've got a real mix. So, we've got a lot of Acroppora up the back there. It's a bit cloudy.

[00:07:49]Here we go. So, we got a lot of Acroppora just there. Then we got some posalopra.

[00:07:57]Um I think it might be a varicosa or damacornus.

[00:08:01]Then we've got a parietes um is it a piety cylindrica? We've got >> maybe >> maybe [laughter] I think I think it's piety cylindrica. And then we got a helopora. Um so one of the things we've had to do with these experiments is you need lots of replication. So basically we got one, two, three tanks per treatment and then within each treatment we've got five different corals of that species and we've got two fragments of that individual colony. So we've got all up I think we've got 15 different genotype. So 15 different colonies from each species and we've got four species.

[00:08:42]So I think all up. So we got 40 corals per tank and we got 12 tanks. So, it's about 480 fragments across these tanks.

[00:08:52]So, that's quite a lot. So, try and keep them alive. Um, they've been in here for a few weeks now, so it's always the hardest part. Um, we just never really know how these corals will respond cuz unlike corals in the aquarium trade, these are locally caught. So, a lot of the corals we brought up, they also had um things like worms um and flatworms on them. So, we've actually had to dip them all and then put them in the tanks. So, they've been through a fair bit already.

[00:09:22]Um, and they're not typically tank hardened like the ones we get. So, being wild caught, um, we expect a little bit of die off just from sort of the collection process. Um, but they're all looking good. So, yeah, hope you guys enjoyed this quick video. Um, and yeah, I'll keep you updated on how it goes.