Erythromycin For BGA

[itafx]

Last Thursday, I started an experiment in my 20 high gambusia fry tank. It has been plagued with BGA. It was so bad the plants get covered and there were webs of cyano between the branches and leaves. The substrate had a carpet of thick BGA covering, perhaps 90% of the area. This happened before and I cleaned everything and did wc but it came back

I finally broke down and ordered an algacide from aquariumplants.com that was supposed to do the trick. When I got it and read the label I found that it was erethromycin.

I dosed according to the directions, turned off the light, and put some black paper on the back of the tank to help shield the tank from sunlight.

Two days later, the BGA seemed to be halted and less healthy, but still there. The fry were fine. I removed and washed off all the plants and replaced them. I also skimmed, washed, and returned the sand.

Now it's been 5 days since dosing. The tank is squeaky clean and the fry are still fine. I'm still watching to see if there are any deleterious effects on the fish or if the BGA comes back, but so far I am convinced it was effective and worthwhile.

I realize some will be concerned about creating resistant strains. To that I would apply an analogy with a patient who is dying of a massive infection. At that point the issue of resistant strains pales in comparison to the need to save the life of the patient.

I would be interested in input from others on this experiment, particularly from folks who have actually tried Erythro as opposed to opinions derived from reading literature.

 

[Zezmo]

That is considered the standard and recomended chemical solution for BGA. Normally Marycyn is recomended, as it is the same antibiotic. It will wipe it out, but it will not keep it from coming back.

 

[itafx]

I guess the spores are in the air and tanks could always be susceptible. If I can get my ecosystem back on its feet, maybe it can resist BGA better in the future.

 

[An t-iasg]

I have used erythromycin, along with a blackout, on my tank 3 or 4 times to get rid of the horrible BGA. It worked like a charm. I didn't even see any "dead" BGA after I removed the blackout garbage bags. I finally fixed the problem by re-directing the flow from the powerhead.

 

[itafx]

That sounds great. How long was the blackout? Did you take the covers off during the blackout to look and see if the fish were in any distress? What did you change about the flow that made the BGA go away permanently?

 

[malkore]

eurythro should be the last step taken against BGA. As with humans, excessive use of antibiotics in a fish tank will result in stronger, resistent strains of bacteria.

BGA treatement steps (assuming that cleaning off all plants, decor, vac'ing out the floating BGA, and doing a massive water change didnt' help):

1. test NO3 - if NO3 is low or 0, that's the reason you have BGA
2. if NO3 is fine, do a 5 day total blackout of the tank. the fish won't starve...or just feed them once after 3 days. NO LIGHT ALLOWED
3. when all else has failed, then medicate.

 

[An t-iasg]

Yes, erythromycin is a last resort. I had rather mild BGA in another tank and a 7-day blackout (no erythromycin) took care of it quite well too.

The tank I was referring to in my last post just had gobs of BGA-cyanobacteria. I have pressurized CO2, and the nitrates were not bottoming out. I would do a water change and syphon the BGA out (it does vaccuum out pretty easily) and three days later the tank was just draped in the cyano again.

Some people report success with a three-day blackout. Since mine was so persistant, for my final blackout and erythro treatment, I did a water change and then just draped the tank for the whole week. You should do a 50% water change before and after the blackout. I wrapped the tank with black garbage bags - sides and top. I took the time to snugly wrap the bags around the corners and make sure the areas of the tank where the filter tubing came out was adequately covered too. I even closed the blinds and put newspapers over the window (it's a small window).

I used 250 mg of erythromycin every other day during the blackout. I let it partially dissolve in a cup of water and then poured it in. I made a "flap" out of the garbage bag on the top of the tank to easily let me open the glass lid for a few seconds.

I didn't have fish in the tank at the time. The tank was a few months old and it always had this cyano problem almost from day 1. I didn't want to get fish until I got the cyano to go away for good. I think if I had fish in there, I would have fed them once during the blackout, very sparingly. Others have reported that it's hard not to peek on the fish, but they were just fine.

I also didn't do any ammonia tests since no fish were present. Since the tank was never cycled (at the time) I don't think an ammonia spike from the death of cycling bacteria would have shown up on the test. However, the decomposing cyano may have caused a slight ammonia rise. I'll never know since I didn't test, and again the reason was that no fish were in the tank.

I can't believe how easy it was to fix the cyano problem, thanks to suggestions of members here! I have pressurized CO2, and the diffuser was misting nicely, but the mist was not directed through the tank. I moved my water pump (it seems silly to call it a powerhead since it's a little Marineland Mini-Jet, but it functions as one) to the top of the tank instead of the bottom. I originally aimed the flow at the bottom front of the tank since most of the cyano was showing up there, but I moved it to the top near the waterline. I put the CO2 diffuser under the pump's intake, so the pump sucked in all the little CO2 mist bubbles and blew them out near the top of the tank. The filter output is beside the pump also, so the CO2 is being ejected into the faster area of waterflow, where it is carried all over the tank. I do need to point out that this is a 10 gallon tank, and there is no "strong" or "fast" flow but the filter and powerhead do combine to give the tank an adequate flow and eliminate dead spots. For my tank, eliminating the dead spots of water flow, maintaining a good CO2 dispersion all over the tank, and maintaining the nitrate levels (especially important since there was no fish in the tank at that time) was the key for me to eliminate the cyano.

Edit - Nice to see you, malkore!

 

[LindaC]

I've been having problems off and on for months with BGA in my 10 gallon tank, I have not used Marcyn due to fish in this tank. I have blacked out the tank twice already and it has cleared the BGA but it always seems to come back.

I do have a powerhead in this tank and it is at the top right near the water level but it does not seem to help. I've tried moving it down only to have the small plants in front blow all over the place. I've tested my nitrates and they are always above 20 ppms, so that's not the problem. I'm at a loss as to why it keeps coming back, it's so frustrating. I do a 50% water change once a week and whenever I see the BGA on my subtrate, I go in and take it right out, but I'm afraid it might get ahead of me again and I'll have to do another black out.

Did I say, I hate this stuff, it has a horrible smell and it's so invasive.

 

[itafx]

What makes the nitrates go away?

 

[An t-iasg]

In a tank with live plants, if the lighting is high enough to drive photosynthesis quickly, the plants will use up the nitrates. If your fish bio-load is not heavy enough to supply the plants, or your tank is heavily planted, then the plants will use up the available nitrate quickly, causing the nitrate levels to fall. I believe a level of 10 ppm is necessary to ward off cyano. If your levels are consistently below 10 ppm, you will probably experience a cyano outbreak. There are supplemental nitrate fertilizers to add to your tank, if necessary, to keep the nitrates from "bottoming out".

 

[itafx]

My experience over the last 6 months matches this pretty well. In my tanks with soil under the top layer of substrate, I have had little or no problems with BGA. The ones that have been plagued are the ones with plain sand and no ferts. I wonder if good fert tabs buried in the sand are enough to keep the BGA away.

 

[Plantbrain]

This assumes what you are using to measure NO3 is accurate........did you calibrate the test NO3 kit or not?

If not, you really cannot say what the NO3 is or not and what was it prior to the BGA, like the week before hand?.........

Go back and either do it right or do not do it.

The other way around this issue, you know using KNO3 and the tank volume how to add 10ppm.

So does the test kit measure a 10ppm increase after dosing this amount?
If not, you know the test kit is way off.

By adding 10ppm, you know that is the minimum NO3.
By adding 2-3x a week 10ppm in a CO2 enriched tank+ weekly 50% water changes, and good ample CO2 and dosing, there should never be any BGA.

It's when folks make NO3 measurement assumptions, do not do water changes, have poor CO2 etc.............

I hear all these horror stories and have for over a decade on the web about BGA, and how folks have absolution in their measurements and routines, yet every time I try to repeat these same conditions I do not get BGA, unless I fail to clean the filters, do not prune, general neglect, or I allow the NO3 to bottom.

I can go back and repeat this and induce BGA in the low NO3 treatment repeatedly. Everytime.

That shows at least a strong correlation that would suggest cause, and with a good NO3 test method, I can further support that.

Now if just the BGA itself is some super vicious type and it just picks on your tanks personally, I have hard time accepting that rational.
So do others that have long since not had algae issues and obviously have had the opportunity to have exposure to BGA and it's air born spores.

There is a cause and folks make assumptions, we all do, that can get them in trouble and make it seem like they are the exception many times, this is not the exclusive domain of BGA, this applies to BBA and many other algae.

If you rely heavily on test kits for measurements, you need to calibrate them and learn how.

If you do not want to bothered with testing the kits, don't bother using using them, there are other methods that avoid their use if you are not going to run a standard to reference them against.

So you have a couple of options, use them right, or not at all.
Well, you can still use them and not calibrate them, but then you are dealing with belief. You cannot say if those readings are correct or not without calibration.

Some claim the test are good enough for their purposes, no, they are not, they have readings all over the place and no brand is infallible, I have found the Lamott and Hach brands to be the most accurate.

But I still calibrate those.

But careful with your assumptions, go back and make sure and think about ways to get around some of those potentially troublesome issues.

I did a dozen BGA blackout + KNO3 test. Everyone of them worked and the BGA did not come back after 30 days.

Algae generally appear in the tanks when the plants are not happy.
They are sign that something needs to be done in the tank, water changes/dosing/more CO2 etc.

It's the same thing 1001 times.
Focus on the plants.




Regards,
Tom Barr

 

[itafx]

Here's an update: It's been about 5 weeks. Still no sign of BGA whatsoever. Ecosystem looks good, plants are thriving, and fish are healthy. Looks like erythromycin was just what was needed in this case.

 

[An t-iasg]

That's good news! Now you can get back to enjoying your tank and the fish!

 

[Plantbrain]

Just make sure to take care of the plants, add the KNO3, traces, KH2PO4, Gh and do those water changes, pruning and filter cleanings.

It's not complex if you keep up on things.
Then things stay stable, if you neglect things, you often have some issues and it takes old fashion work to push them back to a stable state.

Same deal for ecosystem restoration, it's just at a much larger scale.

I do not care if you use the pills or the blackout or both, I care that you learn enough from the outbreak to know to take better care of the plants so you do not have an algae that attacks again and if so, you know what to do to stop it before it gets nasty.

That's where good advice come in.
If all you hear is "add pills" to kill BGA, that's bad advice.

You need to address root causes for algae, and it's almost always poor plant growth.
Look there first, then correct that and then attack the algae.

That's a much better way of going about any algae management.



Regards,
Tom Barr

 

[itafx]

I agree that good care is the important thing. I don't know about adding the chems though. I'm not doing a high light scenario. I'm using substrate ferts that don't have any phosphorous, but are supposed to have everything else needed. The plants seem to be extremely healthy. Since putting the fert tabs in and using a good substrate, plants that had gotten sickly have revived and become brilliant. My amazon sword has had 2 babies that are growing very well, other plants are multiplying rapidly too.

 

[Plantbrain]

There's no sediment I'm aware of that has everything you need except PO4, you need that and Nitrogen as well, which is why you got the bad BGA outbreak.

A little chem knowledge goes a long way, you can make the same argument about learning how to drive, it does make life easier once you know how.

Each step such as adding say K+, or more light or CO2 etc helps to improve growth, but making sure you have done everythign you can will provide the best method and the least issues, it's not hard either.

BTW, why use those fert tabs?

Take some dirt/soil, add alittle water=> mud.
Take mud and oput in ice cube tray, freeze.

Take mud cube out, and place under plants.
It thaws under the plant without making a mess.

Soil has N and P in it and why the tank did fairly well till about 4-10 months later when the soil runs out of the nutrients, namely Nitrogen.

Mud cubes are cheaper.


Regards,
Tom Barr

 

[Sicklid]

I used the maracyn treatment with great results, but part of the results were that I also cut my light in half... I am now able to keep the plants going at a manageable rate (my Rotala must be trimmed weekly to prevent it from taking over!) and I am able to see that the nutrient levels are kept from bottoming as Tom says. When the conditions were out of control to the point where the plants were using up the nitrates so quickly I couldn't stay on top of it, I had BGA at epidemic proportions. It is only by changing the root cause that I say I had "success", not because I used the erythromycin. I am using DIY co2 in a 2.5g with 13w 5000k CF. I can safely say this tank is now "balanced" as I get great growth, and I have not even seen surface algae on my glass, plants, or hardscape for almost three weeks whereas before I had BGA, Thread Algae, and Green surface Algae on everything within THREE DAYS of cleaning.

 

[Puddle]

I used the maracyn treatment with great results, but part of the results were that I also cut my light in half... I am now able to keep the plants going at a manageable rate (my Rotala must be trimmed weekly to prevent it from taking over!) and I am able to see that the nutrient levels are kept from bottoming as Tom says. When the conditions were out of control to the point where the plants were using up the nitrates so quickly I couldn't stay on top of it, I had BGA at epidemic proportions. It is only by changing the root cause that I say I had "success", not because I used the erythromycin. I am using DIY co2 in a 2.5g with 13w 5000k CF. I can safely say this tank is now "balanced" as I get great growth, and I have not even seen surface algae on my glass, plants, or hardscape for almost three weeks whereas before I had BGA, Thread Algae, and Green surface Algae on everything within THREE DAYS of cleaning.

I also have a BGA problem - How long do you keep your lights on for now?

 

[itafx]

In the mean time, I heard a good reason for not using Erythro: it kills off the beneficial bacteria in your tank as well as the BGA, so you have to recycle your tank over again.