GHA, old lights?

akhanf · #1 04/23/2007, 11:37 PM

Hi all,

I have been having a green hair algae outbreak for over a month now.
I have been doing water changes and added a phosban reactor but it doesn't seem to be slowing the growth. I don't run a fuge, but I've recently put some chaeto in my corner overflows. I have not been running any carbon recently either.

Right now, I am showing 10 ppm NO3, 0.1 ppm PO4 using the salifert test kits, but the funny thing is I used to have even higher levels with no GHA (except in the overflows).

My metal halides are about 15 months old (I run them for around 12 hrs a day), do you think a spectrum shift could be causing this outbreak?

Any suggestions are welcome! Thanks!

drummereef · #2 04/23/2007, 11:45 PM

The nitrates are suspect, imo. Your phosphate level is probably reading low because the algae is using it up. The halides are definitely old there's no doubt about it. Most get 9-12 months of solid use from the bulbs before they start to go bad. I'd change the bulbs either way. Where do you think the nitrates are coming from?

akhanf · #3 04/23/2007, 11:55 PM

Nitrates probably came from fish dying; I added a 12 chromis and all but one died in a matter of weeks. Before the outbreak I had 25ppm NO3 with no GHA which is why I wasn't sure if it was the nitrates now.

I'm going to buy some new radium 20k's tomorrow, keep on doing some water changes, and try and pick off as much of it as I can.

drummereef · #4 04/23/2007, 11:57 PM

Ok. What does your filtration setup consist of? Do you use RO/DI water and what is the TDS?

akhanf · #5 04/24/2007, 12:04 AM

RO water, tds 0-2
The makeup water tests at 0 NO3, 0 PO4

drummereef · #6 04/24/2007, 12:05 AM

Do you have any filter socks, sponges, bio-balls, filter floss, etc in the system?

akhanf · #7 04/24/2007, 12:13 AM

Yes I do use a filter sock, which I clean out each water change. It does get fairly dirty; do you think I should take it out and see if that helps?

drummereef · #8 04/24/2007, 12:17 AM

You could try that if you don't end up with a ton of bubbles. Not a bad thing, just asthetic. See if that's the source of the nitrates and go from there. All the bandage fixes for nitrate/phosphate issues will only work for so long. Need to get to the source of the problem to eliminate it.

I also change my DI resin if it reads anything over 0 tds, fwiw. Adding any excess nutrients to the systems won't be helping.

akhanf · #9 04/24/2007, 12:42 AM

I added the filter sock when I put in my sand-sifting goby, but I don't think its really necessary anymore.

Thanks for all the help!

drummereef · #10 04/24/2007, 12:45 AM

Sure thing. Let me know if that helps the nitrate issue. Other than diligent water changes looks like you are doing all the right things so far.

janakaybravo · #11 04/24/2007, 08:13 AM

Wen you say "diligent water changes" would that be 1/4 to 1/3 of the water every two weeks or more often, or more percentage? I change 1/3 of water every two weeks and still have GHA problem. I think the source of mine is a TDS that's reading higher and I need to replace the filters. I have been battling this for the two years I've had my tank and sometimes I want to give up because of the GHA. I have a fuge w/ cheato and skimmer and Phosban reactor and everything I can think of to get rid of it.

Kay

drummereef · #12 04/24/2007, 10:29 AM

janakaybravo - 10-15% weekly water changes is a good number to shoot for. The TDS after you DI stage should be 0. If it's not, I'd change the resin. What is your nitrate level, Jana?

janakaybravo · #13 04/24/2007, 11:43 AM

My nitrates are around 2-3, not even up to 5, and I don't have a phosphate test because I've been told it wouldn't register anything anway. My TDS is reading 6-7 so I'm replacing my filters. But like I said, I've had GHA since about 3 months into having the tank. I have a sand bed that is about 1-2 inches. Do you think having less sand would be better? The GHA actually grows in the sans and makes clumps which I periodically physically remove.

Thanks for your help.

drummereef · #14 04/24/2007, 11:52 AM

How long has the tank been set up, Jana?
How much flow do you have?

The cartriges/resins definitely need to be changed out on your RO/DI system. Like I said before it should be 0 tds after the DI stage.

janakaybravo · #15 04/24/2007, 12:16 PM

It's been set up two years. I have two 820 Seios and one 1500 Seio, or the biggest one, not sure of the numbers. I also have a mag 12 for the return pump. I'm about to get a Vortek to add and I might get rid of one of the Seio's.

drummereef · #16 04/24/2007, 12:22 PM

Good, you have plenty of flow then. Sorry to ask so many questions, but what skimmer are you running and when is the last time you changed your lights?

janakaybravo · #17 04/24/2007, 08:46 PM

Thanks so much for your help. I'll answer any questions to help me get to the bottom of this. I have an ASM G3 and I changed my MH's about 4-5 months ago, XM 10K's and I have 2 actinic blue strips that are six months old that I'm replacing this week.

The TDS meter is reading 6 right now, and I know that's high so I'm getting more filters in.

Kay

drummereef · #18 04/24/2007, 09:38 PM

Ok, that narrows it down. I think the majority of your problem is from the RO/DI then. Everything else checks out. It seems like the weak link as it stands. I'd change out your phosphate media again, and maybe run some PHOSaR in the phosphate reactor. It's supposed to be really good media right now.