Hello, just wanted to share a helpful tip I learned about dosing lanthanum chloride into the skimmer cup. If you don’t care to read the rest of the post here is what I have learned:
Do not dose/drip into the top of the cup. Installing extra tubing to dose further down in the skimmer body is much more effective! (Mine is sitting about 1/2inch above water line with skimmer off now)
Here’s my experience. I’ve been struggling with high phosphates in my 210g reef for quite some time. For about a year now I’ve been carbon dosing heavy with kalk saturated vinegar to keep nitrates undetectable, but phosphates have been a constant struggle to keep low. I tried gfo, but it was never enough in the amounts I could afford, I’m guessing due to the amount my rocks were leaching due to year+ of sky high phosphates. I had better success with aluminum based media brightwell extrax phos bringing down levels more quickly/noticeably but they would just come back up after treatment. I was also concerned with possibility of leaching aluminum into the water and irritating my monster sized toadstool leather so I didn’t want to continue that method. Throughout all of this I tried dosing nitrates. I run a large cheato refugium and thought extra nitrates would help remove some phosphates, assuming nitrate was a limiting nutrient in the biological export processes. This also didn’t seem to help much.
I finally landed on lanthanum chloride as being a good cost effective way to fight back against phosphates. Most people drip into a 5 micron filter sock into the sump, apparently the sock gets clogged within hours so I didn’t want to go down this route. Thru research I read some people had success dosing into the skimmer intake, but this causes white buildup in the skimmer pump and possible premature failure so I didn’t want to do that either. I also read some people were dosing/dripping directly into the top of the skimmer cup so I figured that was the method I would try. I chose two little fishies phosban-L as my lanthanum chloride product. This is essentially a more watered down version of lanthanum chloride than say commercial pool additives.
Initially I bought the iv type drip bag and was dripping small amounts daily. This was definitely having some effect on lowering phosphates but was a chore mixing it up daily so I decided to put it on a dosing pump at a 29:1 ratio rodi: phosban-L dosed hourly. For the next 50 or so days I ran like this testing frequently and continuing to raise my dose to try and keep phosphates in check. All the while my phosphates kept slowly creeping up. It finally dawned on my that I must be doing something wrong as I was dosing way too much lanthanum chloride not to see any noticeable effect.
About 4 days ago I tried adding a longer tube of rigid rodi tubing to reach further down in the skimmer cup. Since then my phosphates have been going down 0.025ppm daily. A gigantic improvement, and now I’m in normal range and reducing my daily dosage. My guess is that more dwell time with the water before being skimmed out is the reason. It also could be coincidental that my rocks have decreased leaching phosphate at the same time but I highly doubt it based on speed of reduction I instantly saw after this small change to my setup.
Well anyway this ended up being a long post but I just wanted to share this observation with anyone considering this method of phosphate reduction. If someone had told me this I could have saved a lot of time. Let me know if you have any questions and I will do my best to share any specifics to anyone curious.
Do not dose/drip into the top of the cup. Installing extra tubing to dose further down in the skimmer body is much more effective! (Mine is sitting about 1/2inch above water line with skimmer off now)
Here’s my experience. I’ve been struggling with high phosphates in my 210g reef for quite some time. For about a year now I’ve been carbon dosing heavy with kalk saturated vinegar to keep nitrates undetectable, but phosphates have been a constant struggle to keep low. I tried gfo, but it was never enough in the amounts I could afford, I’m guessing due to the amount my rocks were leaching due to year+ of sky high phosphates. I had better success with aluminum based media brightwell extrax phos bringing down levels more quickly/noticeably but they would just come back up after treatment. I was also concerned with possibility of leaching aluminum into the water and irritating my monster sized toadstool leather so I didn’t want to continue that method. Throughout all of this I tried dosing nitrates. I run a large cheato refugium and thought extra nitrates would help remove some phosphates, assuming nitrate was a limiting nutrient in the biological export processes. This also didn’t seem to help much.
I finally landed on lanthanum chloride as being a good cost effective way to fight back against phosphates. Most people drip into a 5 micron filter sock into the sump, apparently the sock gets clogged within hours so I didn’t want to go down this route. Thru research I read some people had success dosing into the skimmer intake, but this causes white buildup in the skimmer pump and possible premature failure so I didn’t want to do that either. I also read some people were dosing/dripping directly into the top of the skimmer cup so I figured that was the method I would try. I chose two little fishies phosban-L as my lanthanum chloride product. This is essentially a more watered down version of lanthanum chloride than say commercial pool additives.
Initially I bought the iv type drip bag and was dripping small amounts daily. This was definitely having some effect on lowering phosphates but was a chore mixing it up daily so I decided to put it on a dosing pump at a 29:1 ratio rodi: phosban-L dosed hourly. For the next 50 or so days I ran like this testing frequently and continuing to raise my dose to try and keep phosphates in check. All the while my phosphates kept slowly creeping up. It finally dawned on my that I must be doing something wrong as I was dosing way too much lanthanum chloride not to see any noticeable effect.
About 4 days ago I tried adding a longer tube of rigid rodi tubing to reach further down in the skimmer cup. Since then my phosphates have been going down 0.025ppm daily. A gigantic improvement, and now I’m in normal range and reducing my daily dosage. My guess is that more dwell time with the water before being skimmed out is the reason. It also could be coincidental that my rocks have decreased leaching phosphate at the same time but I highly doubt it based on speed of reduction I instantly saw after this small change to my setup.
Well anyway this ended up being a long post but I just wanted to share this observation with anyone considering this method of phosphate reduction. If someone had told me this I could have saved a lot of time. Let me know if you have any questions and I will do my best to share any specifics to anyone curious.
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