Use of Lasers in Controlling Pest Algae and Corals

[TheFishMan65]

For those that may not understand I will try and explain heat transfer in laymans term (so you can understand my concerns). Please not I am not an expert so if I get something wrong please correct me.
In an ideal case the LED will run at some temperature say 100 degrees. It will conduct perfectly to the heat sink the the heat sink where the LED touches will be 100 degrees. The other end of the heat sink will source the heat somewhere lets say 0 degrees. in the ideal case that side would be 0 degrees. The center of the heat sink roughly 50 degrees.

Water is a much better conductor of electricity so it keeps that side of the heat sink pretty much at water temperature. If the heatsink can't transfer the heat fast enough though the LED could reach 200 degree, the middle 100, but the water side is still water temperature.

There are two issue how fast can the heat be moved from the LED and how fast can it be dissipated. Water dissipates faster, but if the heat can't get away from the LEDs it won't matter (to some degree).

Hope this helps.

[CalmSeasQuest]

Thanks Thefishman65. I certainly understand and agree with the concern. That said, I'm comfortable with extending the duty cycle when used submerged. At next use, I'll take some temp reading with my IR thermometer at various points. I *think* it will be OK as I can't detect any temp increase - even in the front of the laser where the diode resides opposite the heat sink. It's certainly possible I could kill it, but at least it will have died in the name of science

I've been getting a lot of questions regarding the effectiveness on specific pests. Here's what I've noted so far. Listed in order of ease of eradication (easiest to most difficult)...

• Hydroids
• Aiptasia (very easy to eradicate as long as you have line-of-sight to the attachment point.)
• Valonia
• Clove Polyps
• GSP
• Vermetid snails (The small ones are simple - The large ones require very long lase times - and you have to focus at the base, well behind the snail when extended.)
• Majano
• Red Turf Algae
• Xenia

My "focus" has been on Xenia as all else has been relatively simple to eradicate. Xenia is proving to be the greatest challenge. I agree with jrpark22000s comments - It typically takes multiple sessions over the course of a few days to completely kill it. You basically have to lase it until it's little more than a "blob" to prevent it from regrowing.

The very fine, "wispy" algaes such as hair and bryopsis are also resistant, seemingly due to how effective water is at cooling. Even they can be destroyed by focusing on the attachment points, (especially in small patches) but it takes much longer and would not be practical for large amounts.

I have also found it useful in "pruning" SPS to eliminate encroachment and the resulting chemical warfare (especially Montis.) I theorise it might also be a useful in cases of RTN - in essence, cauterizing a border, thereby separating the healthy tissue from the area of RTN. Thankfully I haven't had it occur to test.

I've also been asked about Zs or Ps. While I haven't targeted any, I see no reason why it would not be effective. The general rules seems to be that lighter colored - larger mass items will take longer to eradicate. Any coral or pest I can imagine could be destroyed by a laser. It's simply a matter of how much lase time would be required.

[CalmSeasQuest]

One other observation - After extended lasing session (Xenia) I noted that there is about a 20 point drop in ORP (440-420) which gradually recovers over the next few hours. I'm uncertain what is causing this, but it seems reasonable that organics might be released into the water column.

I've only noticed this thus far when lasing Xenia and I have not noted any negative impact form any other corals in the tank (including those within an inch of the targeted pests.) I run ROX 0.8 carbon on a continual basis.

[CalmSeasQuest]

Both lasers (waterproof and non) continue to work very well. I find that I am working more from outside of the tank, alternating duty cycles with both lasers.

Every pest targeted except for Xenia has been easily eradicated with the laser. Xenia continues to be a challenge. I've been able to contain it, but haven't had the patience to completely remove the larger patches.

I'm convinced the laser can be a very valuable tool as long as safety protocols are observed.

[wilsonreefs]

Originally Posted by CalmSeasQuest

Both lasers (waterproof and non) continue to work very well. I find that I am working more from outside of the tank, alternating duty cycles with both lasers.

Every pest targeted except for Xenia has been easily eradicated with the laser. Xenia continues to be a challenge. I've been able to contain it, but haven't had the patience to completely remove the larger patches.

I'm convinced the laser can be a very valuable tool as long as safety protocols are observed.

OK Tom,

You either need to come to my house and get rid of my mojano, actually not very much at that (at most maybe 10 stalks), loan me your lasers, or last but not least.....tell me where to buy them. Very good information, Thanks for the extensive research and sharing with everyone. Well done!

Carl

[BuckeyeTodd]

Has anyone noticed majanos returning. I'm wondering when they pop, if they release spores of some sort.

[ivans75]

wow u guys in the states are really something lol using a star wars weapon to eliminate aipstasia and the likes. OmG...Sorry but with whatever safety policy that you guys are discussing I am not gonna use this equipment in my tank. It just sounds stupid. It does amaze me some people come up with a thought like this. It's not that hard to get rid of pests. Plus how much does it cost? I believe I can profesionally paint my whole house to get one of those laser in my doorstep.

[CalmSeasQuest]

Originally Posted by wilsonreefs

OK Tom,

You either need to come to my house and get rid of my mojano, actually not very much at that (at most maybe 10 stalks), loan me your lasers, or last but not least.....tell me where to buy them. Very good information, Thanks for the extensive research and sharing with everyone. Well done!

Carl

Thanks Carl I purchased the 1.7W through Survival laser (very simple assembly required.) The 1.2W was from Lazerer and ships assembled, but from Hong Kong so delivery times are Longer. Between the 2, I prefer the Survival Laser as for our purposes, the higher power output the better. Another grat resource in the Laser Pointer Forum. You'll find lots of valuable information and advice and often lasers for sale at much lower prices.

Originally Posted by BuckeyeTodd

Has anyone noticed majanos returning. I'm wondering when they pop, if they release spores of some sort.

I didn't have many Majano in my tanks to to extensive testing on, but I believe they will respond similar to Aiptasia which I have observed very high kill and no return rates. My process is to start at the mouth and laze your way down to the base. In "theory", the intense heat kills any planula released.

Originally Posted by ivans75

wow u guys in the states are really something lol using a star wars weapon to eliminate aipstasia and the likes. OmG...Sorry but with whatever safety policy that you guys are discussing I am not gonna use this equipment in my tank. It just sounds stupid. It does amaze me some people come up with a thought like this. It's not that hard to get rid of pests. Plus how much does it cost? I believe I can profesionally paint my whole house to get one of those laser in my doorstep.

The use of a laser for these purposes clearly isn't for everyone. It's costly and requires serious attention to safety protocols. It can be however, a valuable tool for those with tanks from which access and removal of affected pieces is impractical. Clearly in your situation, it might not be a viable option, but I would disagree with your assertion that the practice is "stupid".

Having just paid significantly more to have my home painted, I am a bit jealous you can have your entire home painted for less than $200 US

[Wrench]

I'm having a hard time killing mojanos and the aptasia that I lase are coming back in a couple of days. I may not be zapping 'em long enough though as I'm concerned about exceeding the duty cycle and frying my diode.

[CalmSeasQuest]

Originally Posted by Wrench

I'm having a hard time killing mojanos and the aptasia that I lase are coming back in a couple of days. I may not be zapping 'em long enough though as I'm concerned about exceeding the duty cycle and frying my diode.

I haven't encountered any problem other than with large patches of Xenia. I'd estimate I spend less than 10 seconds on even the largest Aiptasia after which there is virtually nothing left but a bubbling, gelatinous "blob".

What type of laser are you using (Mfg, wattage, wavelength, lens and duty cycle) and how from the target is the laser?

Remember to clean the tank glass or acrylic before lasing and turn off all water movement as it will increase the effectiveness. If the focus is off by the slightest, it will dramatically decrease the effectiveness of the laser.

[ivans75]

Originally Posted by CalmSeasQuest

The use of a laser for these purposes clearly isn't for everyone. It's costly and requires serious attention to safety protocols. It can be however, a valuable tool for those with tanks from which access and removal of affected pieces is impractical. Clearly in your situation, it might not be a viable option, but I would disagree with your assertion that the practice is "stupid".

Having just paid significantly more to have my home painted, I am a bit jealous you can have your entire home painted for less than $200 US

Awww...calmsea, my apology I'll take it back. Should not say stupid...my bad. I had a bad day. To think it over again, yes it can be quite helpful in a big tank where one is quite hard to reach. And it only cost 200 bux???? I gotta get one of those lol thought it cost thousands hahaha...omg pardon my ignorant...my apology again...

[Ralph ATL]

If have small tufts of Bryopsis here and there after eradication, as I do now, would it work? I am just treating those areas with a kalk paste with Lime/RO/H2O2 and seems to be working to get the rest little stuff....

[Gangrene]

Okay, Time to chime in...

"Regulation can make it more difficult to obtain such items for the average idiot, and sometimes that is all it takes. I stand by my desire for greater restriction on these weapons."

Agreed. I think they should be totally illegal unless a person will take a year worth of classes and gets a very hard to get, yearly tested, license and every laser should have a serial number and have to be registered. Put a life sentence on violation or ownership, and that should be a suitable deterrent and if not, we'll not have to worry about that individual any more... I'm not worried about the people on this forum. I'm worried about some criminal using this on the streets(blind people can't identify suspects), the thousands of pilots affected yearly, or cruel and unusual treatment of people or animals... lets just "las" the dog for fun... just to name a few... these are not toys. Then there is the slippery slope... Aptasia now, that fish is dying(put it out of it's misery), what else can we use this thing on? Oh, the videos that will appear on youtube... I can see them now. Dying Eel vs. 1800 Laser... Just about as cruel as a live animal in a microwave if you ask me... Not much good can be had from allowing this to the general public. I know people who have such lasers now... I know them, and frankly I'm scared. He was telling me how it can travel through the air 20 miles toward space, hit planes, cuts stuff like a light saber, etc... The man is frankly a grown child...

I'm pretty sure we can build some way to radiate the aptasia as well... Lets pick up some equipment they use to radiate tumors and use it to clean our tanks. If we can pinpoint a tumor we can hit an aptasia. Just remember the correct safety, lead vests etc... What?!?! That is the level of absurdity I'm pretty much hearing here. It's not too removed from what is being discussed now. Lasers, Seriously? There are laser sights on guns, but not paintball markers. That's because the laser sight(red) on a gun is damaging, but that is considered secondary to the damage that bullet is going to inflict. This is reversed on a paintball marker. The laser(even at that power) will do more damage to your eye(wearing proper equipment) than the paintball can do, so it is not allowed. Some similar rule should be in effect here I would think... kill a minor pest that is really only a visual blemish vs. permanently blind someone. The logic seems simple to me.

"I highly doubt that there are many cases of the drunken nitwits buying high power lasers and pointing them at aircraft.", BeanAnimal

Although I highly respect BeanAnimal, I'd have to say that statement is pretty baseless and this is a HUGE problem... Here is an article: http://www.npr.org/blogs/thetwo-way/...-times-in-2010

2800 incidents in 2010, doubled since 2009 and without laws in place, will likely to increase even more!

Here is an article about about the Problem in LA, where they had 102 incidents in 2010: http://www.npr.org/2011/01/24/133171...-Laser-Attacks

These things scare me way more than a gun. They reflect and bounce around a room, can nail a plane up in the sky, etc...? Bullets don't typically reflect back at you...

Like someone said earlier... Someone in the aquarium hobby, is more than likely, now going to go blind at least in one eye... People will spread misinformation, people will lack on safety or whatever and this is almost a certainty seeing as how many people are interested in buying them in this thread alone, not to mention that local reef meeting with the sunglasses... I can see where this is headed. It's a tough call here for the mods, continue the thread and increase the number of blinded, or pull the thread and not get the safety concerns out there. I think it should be kept up considering the cat is already out of the bag. I think I've said enough there... I'd like to help avoid this probable outcome and I'm going to try and advance the safety practices to help minimize the damage people will inflict on themselves and others. Time for something a little more constructive than simply addressing concerns....

I suggest the following... Build a blind to stand behind as a shield. make it as tall as your tank. It would have three sides and go around your tank assuming it is against a wall. It should be of a material and thickness able to absorb a direct blast for a few seconds. Cut a vision slit to look through with your glasses. All reflections should be handled by the shield and you won't catch a reflection in the arm, neck etc... Continuing... create a housing similar to the one shown earlier... I'm envisioning a narrow pipe of some form(not pvc for reasons stated earlier), several inches in length attached to the end of the laser. This should block any visibility of the laser source. Cut a hole in the blind just large enough for the "laser blind tube" to be inserted through. Insert a couple inches through take aim and use it as minimally as possible to get the job done. Alternatively you could attach a arm, to the blind, with a screw tightening mounting clamp to lock the laser, in place, onto a target and avoid a possible "slip up". It would have the advantage of avoiding any minor hand shakes that might cause your laser to hit a nearby neighbor. You could position the arm with the weak targeting laser mounted. Once a good position is found, lock the arm into position and swap in the more dangerous laser into the mount. I could draw something up as a model of what I'm envisioning, ask if you'd like me to put something together.

Good Luck and stay safe with your ventures, safe to say I'm avoiding the laser methods.

[Ron Reefman]

Gangrene, I sure hope you are at least as hard on gun ownership as your are on the owning and using of lasers? You're worried about somebody being hurt by a laser while multiple hundreds of people get killed in gun accidents every year, not to mention on purpose killings. This is a matter of personal responsibility. And just so you know where I'm comming from, I now own 2 of these lasers (similar to CalmSeaQuest) and not only do I not own a gun, I don't care for them either. But as long as people are going to own them and use them (guns or lasers), it's all a matter of personal responsibiliy as to how they use them, safely, carelessly or illegally.

[CalmSeasQuest]

Gangrene,

Thanks for sharing your thoughts. I'm not going to spent much time with specific responses as most of the items mentioned have been discussed as nauseum throughout the course of this thread.

I will say that as a 30 year veteran IFR rated pilot, I certainly understand the risk to aviation and support the resulting Federal and State laws making such actions illegal but ...your argument would require the banning of virtually all laser-equipped devices. From an aviation standpoint, even low power lasers, including laser pointers that many of us use in daily business activities could impact a flight crew on short-final (the most critical part of any flight.)

It should also be noted that the vast majority of reported laser incidents that I am aware of were green (~532nm) lasers which are useless for our purposes in marine aquaria.

I promote treating high power lasers as a handgun to the extent of keeping them locked and out of the reach of others, especially children that may be in the home but, beyond that the comparison weakens. All that is required to provide protection from the lasers discussed in this forum is proper eye protection for everyone within range of the laser. A far different scenario than protecting someone from a bullet strike with far greater consequences.

[CalmSeasQuest]

A small update - I lased a couple of larger Aiptasia about 2 weeks back and noticed that both were regrowing. I believe the regrowth was a result of my failure to gain access to the foot of the polyp. These polyps were attached to the stems of Frag plugs that were angled in such a manner I didn't have a "clean shot" at the attachment point and I didn't take the time to rotate them for better access.

I've had great success up to this point, so I believe it was a case of user error. The key to preventing regrowth seems to be super-heating the entire polyp. I believe having the highest power output / longest duty cycle laser provides for increased success. To that end, I ordered a custom made 2W+ 445nm laser with increased heat-syncing and a G-1 lens that should work very well for this process. It won't be complete for a couple of weeks, but I'll post updates thereafter. Here are a couple photos of the new laser design...







The addition of this 3rd laser will allow for alternating the lasers making quick work of any pests without being limited by duty-cycle concerns.

[usfpaul82]

has anyone tried this on mushrooms? i can get most of my 'pest' mushrooms out of my tank by other means, but there are always a few that I can't get to that start to colonize,

[Ron Reefman]

I haven't tried it, maybe Tom (calmseaquest) has. In the limited amount of work I have done on anything other than aiptasia and majano, I've found the more opaque it is, the smaller it is and the more zoa like polyp it is, the better it works. It takes out individual polyps of good size palys, but it had little affect on GSP base material. I think there is little fluid in the GSP base for the laser to heat up, and it also can transfer heat to thr rock. But I'm just guessing. Like I said, I use it on aiptasia and majano anemones.

[salty joe]

I've recently read a couple threads about snail eating worms. Think a laser would do the trick on worms? Apparently, they can quickly retract into the rock. I'm thinking that enough head shots would do them in.

[CalmSeasQuest]

Here's the latest addition which ships on Monday. The photo shows it's power output being measured using an LPM (Laser Power Meter.) More than 2.2W of 445nm should make quick work of most any pest.



This one has extensive copper heat-syncing that should also provide for a healthy duty cycle.

[CalmSeasQuest]

I just received word from the the designer/builder that it might be possible to include a diode capable of 2400mw in this host. That would make it the highest output single diode handheld I have ever seen. It should dramatically improve the performance for our purposes.

[SeanT]

Fascinating thread.
It's hard to completely side with either side of the discussion safety -v- pest eradication.

The fact of the matter is as humans (especially Americans) we always want the easiest, most efficient way to accomplish tasks.
As reefers, we love toys and technology.

The genie is out of the bottle and will never be put back.

I may try this myself if I ever get aiptasia again.

Besides posting just to hear myself, the only advice I can proffer is to be careful.

Sean

[CalmSeasQuest]

Originally Posted by SeanT

Fascinating thread.
It's hard to completely side with either side of the discussion safety -v- pest eradication.

The fact of the matter is as humans (especially Americans) we always want the easiest, most efficient way to accomplish tasks.
As reefers, we love toys and technology.

The genie is out of the bottle and will never be put back.

I may try this myself if I ever get aiptasia again.

Besides posting just to hear myself, the only advice I can proffer is to be careful.

Sean

Thanks Sean - Safety is clearly the main priority. Cutting through all the "noise", I've found using the laser safely is relatively simple.

• Appropriate eye protection for EVERYONE within range of the laser
• Control the environment - Allow no one into the controlled space without appropriate eye protect and do not allow the laser to escape the controlled space (windows, doors...)
• Secure Storage - Batteries removed, locked storage when not in use.

[JT3069]

[language]

the ides of lasers on pest in awesome, but not for me (my eyes are already bad)
but every person has the right, or freedom to choose for themselves

interesting work, looking forward to updates

o_o

[SeanT]

I would love to see a video of you lasing Valencia, and then a few days later video if possible.