# green water - need UV or diatom filter?



## JRJ

My 46 gallon has been afflicted with green water for the last 4 weeks. Most plants seem healthy, Nitrate, Phosphates, etc., seem normal, and 70% water changes don't change the situation much.

I'm on the verge of buying a UV unit - which I really don't want to spend the money on. I do have an old Magnum HOT filter. Does using that with diatom powder work just as well?

Also... Any suggestions on what I might do to prevent this crud from coming back if I do get rid of it?

-Russ


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## stcyrwm

I've had really great luck with the HOT Magnum with diatom powder. I know MatPat has too because he was the one who told me about it.

Bill


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## Rob Tetrazona

I've used my Magnum 350 w/ the Micro cartridge and diatom powder to reduce the green water, but it took a couple of HUGE water changes along with that to get rid of it completely. I had to change the powder several times, it took several hours, and it was a severe PITA! I think it probably could have been done more effectively. I have a SoilMaster sized bag of diatom powder if you go that route.

I think my green water started from disturbing the substrate too much and not doing a water change immediately afterwards.


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## MatPat

I think Rob nailed the cause of your GW. I can get GW anytime I want by uprooting a bunch of plants and not doing a water change afterwards. 

My HOT Magnum works wonderfully on my 75g when I have cases of GW. If I notice the beginnings of GW in the evening, I put the HOT on the tank and run it overnight. It is usually clear in the morning. Sometimes I do have to run it all the next day to get the waer crystal clear. 

It sounds like you have a good case of GW. What I would do is a large WC to get as much out of the tank as possible. Then I would start the HOT running on the tank and mix up 2 ounces (1/4 cup) of diatom powder in 8 oz of water. Put the container of water and powder under the intake of the HOT and uncap it. It takes a minute or two but the HOT will eventually suck the mixture into it. If you're impatient like I am, make sure your container has a large enough hole and put the intake of the HOT right into the container. Works like a charm


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## Rob Tetrazona

Hey a double posting, great!!! My Time-Warner Road Runner (cable modem) connection sucks so bad that I can barely surf or post to message forums very well anymore.

Boycott Time-Warner Cable. They are crooks and their product sucks balls!!!

Sorry to trash your thread Russ.


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## MatPat

Hey Rob, 

I fixed your double post  

Unlike GCAS, you can go in and delete your post using the edit function. I don't think it is only your connection today. I am very slow also and not just on here. There have been several sites today that have loaded very slowly for me. Must be the rainy weather or something.


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## stcyrwm

rwoehr said:


> I have a SoilMaster sized bag of diatom powder if you go that route.


Is this diatom powder made for an aquarium diatom filter? I used diatom powder from a pool store once while I was waiting for a mail order and it was the only time my water wasn't crystal clear within a couple hours.

Bill


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## Rob Tetrazona

stcyrwm said:


> Is this diatom powder made for an aquarium diatom filter? I used diatom powder from a pool store once while I was waiting for a mail order and it was the only time my water wasn't crystal clear within a couple hours.
> 
> Bill


Bill,

Yes, I do have the pool version. From what I can remember, it's supposedly the same stuff. Let me find the link....


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## MatPat

Very interesting Bill! I have heard a few people say the HOT did not work on their tank and it makes me wonder if maybe the "pool" diatom powder is a larger grade.

Rob, if we can remember, why don't we each bring a 1/4 cup of our diatom powders and compare the two at our next meeting. We may have to do it outside since BW3's may not be too excited about two guys carrying around little baggies of white powder  We are still meeting at BW3's aren't we?


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## J.Sipes

I am using a Vortex D-1 diatom filter with powder from a pool supply house and I must say it works great. I get GW in my soil tanks if I uproot plants. I didn't think I had any in the last week but ran the filter on it just for kicks and the powder turned green overnight. I do switch the powder out often if the tank is very cloudy that I am polishing,other than that i use the powder multiple times...
I don't recall if they make different grades of Diatom powder or not,maybe that could be the problem and if so it would be in the hands of the supplier to which grade they sell.
I have purchused some at HD in the past and ran it in a HOT filter and it worked great.
HTH Russ,Good luck with the GW.
BTW I have some crypts for you, let me know if you are coming to the next meeting,it will give me a little more time to cultivate them a little more.


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## Rob Tetrazona

This is all just chatter, but:

SWOAPE Diatom Powder Link


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## Rob Tetrazona

MatPat said:


> Hey Rob,
> 
> I fixed your double post
> 
> Unlike GCAS, you can go in and delete your post using the edit function. I don't think it is only your connection today. I am very slow also and not just on here. There have been several sites today that have loaded very slowly for me. Must be the rainy weather or something.


Thanks, Matt.

I'm just agravated w/ my ISP. Anyway, Time-Warner knocked $10 off my bill for the next 6 months and credited me $7. Now I can get that operation for my mother! However, the dork at the ISP couldn't figure out how to transfer me and now I get a busy signal everytime I call the support line, so the problem still exists. Ugh!


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## Rob Tetrazona

MatPat said:


> Rob, if we can remember, why don't we each bring a 1/4 cup of our diatom powders and compare the two at our next meeting. We may have to do it outside since BW3's may not be too excited about two guys carrying around little baggies of white powder  We are still meeting at BW3's aren't we?


Roger, Roger. Got your vector, Victor. Over Rover.


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## Simpte 27

I ue a UV light. Works wonders in 24-48 hrs depending on how bad the tank was. Also good for green dust.


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## JaySilverman

Whats cheaper. A UV unit or diatom filter. If using diatome powder do you need a special HOT filter or would any do?


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## MatPat

A HOT magnum, while not actually a "diatom filter" will work. You do need some type of canister filter without any bypass. Eheims, Fluvals, and most other canisters do allow water to bypass the media. I thnk this is what gives them their long service life. The Magnum 350 and HOT Magnum do not have any water bypass and will actually clog once the micron cartridge gets packed. 

There is also the Vortex and another brand of Diatom filter that I can't think of right now  Both brands may be reviewed in the Reviews Section.


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## JRJ

Folks,

Thanks for the replies and sorry to be abscent for my own thread (busy work week).

I did a 70% water change and I'm leaving the lights off for a couple of days. I'll see what happens. Next the HOT/diatom method (thanks for the instructions, Matt). I assume I should suspend ferts during the lights-out period. If that doesn't work, I'll buy a Turbo-twist UV. I hear that UV units fry trace elements, right?

-Russ


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## MatPat

One thing I did not mention was the blackout. 3 days or so of a covered tank will usually rid it of GW. Good thing about blackouts is that they are free!!! No filters to buy, no powder to purchase and no electricity. I guess they actually save you money in the electricity department 

I wouldn't dose during the blackout (did you add anything back after the water change) and definately turn off the CO2!


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## JRJ

CO2 is off. The only thing I dosed was Seachem Trace elements, which is what I think my Cyperus helferi has been missing. I finally got some yesterday in the mail.

I didn't have time to get something to black the tank out, so this is a lights out only. I lost a Sterbai cory and one of my two big Amano shrimps due to what I assume was oxygen deprevation. Damn. Since I turned off the lights the plants weren't giving off much oxygen, which I totally underestimated. Put in an airstone and everybody stopped gasping.

I'll let you-all know what happens. Anybody know where I can get some aquarium diatom powder locally? Checked two stores to no avail.

-Russ


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## Rob Tetrazona

I can give you some DE for free. I purchased a larger than needed bag from Watson's for $12.


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## MatPat

A lights out only blackout may work if the tank is in the basement but I don't think you will hve much luck if it gets any natural light. 

Sorry to hear about the Cory and Amano Shrimp. I have only done one blackout and did not think to add an airstone either. I guess when we limit surface disturbance for CO2 tanks it really hurts to not add an airstone when we turn out the lights! I will definately keep this in mind for the future. 

I had to order my diatom powder but looks like you have a source already and the price is right too


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## JRJ

rwoehr said:


> I can give you some DE for free. I purchased a larger than needed bag from Watson's for $12.


Thanks Rob, I'll be in touch if the lights out doesn't work.

-Russ


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