Phosphates won't go down!

[Harris3005]

I've been having trouble with green hair algae and cyano in my DT and recently bought a Hanna Phosphorous ULR checker in order to get a better understanding of what was going on. My salifert phosphate kit was reading as zero but I knew this couldn't be the case. About 4 weeks ago when the checker arrived it was giving a reading of 59ppb phosphorous which equates to 0.181ppm phosphate.

In the last four weeks I have added a new reactor with rowaphos, a diy chaeto algae reactor and I've done two 25% water changes, the second of which was yesterday. Today I tested again but it's only gone down by 2ppb to 57ppb phosphorous or 0.175ppm phosphate. I was expecting it to have fallen more than that after the changes I've made and the water changes, is this a normal reduction?

Nitrates are zero on salifert kit which from what I've read could be fueling the cyano?

I have bought 10 grams of lanthanum chloride but I've been a bit scared to use it so far as I've heard tangs can suffer adverse effects from the solid that it creates when binding phosphates. Would you use this to lower the levels of phosphates I have given above or is this a bit of an extreme measure to take?

Sorry for the long post I just thought it best to give as much info as possible!

 

[hijinks7]

do you use RODI water? If so have you checked the TDS of the "clean" water

What type rock did you use and how old is the tank?

 

[Randy Holmes-Farley Verified Community Expert]

Just to clarify the wording, low/undetectable nitrate doesn't fuel any organism. It may inhibit some organisms more than cyano and might allow cyano to outcompete them. Additionally, if you have a lot of green hair algae, nitrate may be low just because the hair algae and the cyano are sucking it up fast.

That said, using enough GFO can certainly help drop the phosphate, but I would not assume that will eliminate the algae. I'd generally aim for about 0.02-0.03 ppm phosphate (7-10 ppb P) since going lower can risk worse issues such as dinos.

How much GFO are you using and what is the tank size?

Huge amounts of phosphate bind to rock and sand, and it can take a while to deplete that reservoir.

 

[Harris3005]

do you use RODI water? If so have you checked the TDS of the "clean" water

What type rock did you use and how old is the tank?

Yeah I use a 150gpd 4 stage RODI and i get 0 TDS water. My water is only about 39 TDS out of the tap so it doesn't take much to get it to zero after Going through the RODI. I used a mixture of live rock and carib sea life rock. The live rock is about 2 years old as it came from my previous tank and this tank has been up and running for about 10 months maybe more.

 

[Harris3005]

Just to clarify the wording, low/undetectable nitrate doesn't fuel any organism. It may inhibit some organisms more than cyano and might allow cyano to outcompete them. Additionally, if you have a lot of green hair algae, nitrate may be low just because the hair algae and the cyano are sucking it up fast.

That said, using enough GFO can certainly help drop the phosphate, but I would not assume that will eliminate the algae. I'd generally aim for about 0.02-0.03 ppm phosphate (7-10 ppb P) since going lower can risk worse issues such as dinos.

How much GFO are you using and what is the tank size?

Huge amounts of phosphate bind to rock and sand, and it can take a while to deplete that reservoir.

The tank is around 600 litres including the sump and I've got around 200 grams of rowaphos in the reactor.

Do you think lanthanum would help get it down to a more acceptable level and allow me to maintain that level through the gfo and water changes or is it not worth the risk? I also have chemi clean here for the cyano but I have been wary of using either and trying to get things under control without using either the lanthanum or chemi clean as they both frighten me a wee bit!

 

[Randy Holmes-Farley Verified Community Expert]

The tank is around 600 litres including the sump and I've got around 200 grams of rowaphos in the reactor.

Do you think lanthanum would help get it down to a more acceptable level and allow me to maintain that level through the gfo and water changes or is it not worth the risk? I also have chemi clean here for the cyano but I have been wary of using either and trying to get things under control without using either the lanthanum or chemi clean as they both frighten me a wee bit!

How long has has the GFO been in?

have you tried to measure the reactor effluent? That's the easiest way to see if it is working or depleted.

The lanthanum is likely to be fine (especially if you catch the solids), but if you have GFO already, I'd use that.

 

[Halal Hotdog]

Lanthanum chloride works very well with combating high phosphates. Like any additive it has pros/cons. I have used it and have had great results, also does not require a reactor.

 

[Harris3005]

How long has has the GFO been in?

have you tried to measure the reactor effluent? That's the easiest way to see if it is working or depleted.

The lanthanum is likely to be fine (especially if you catch the solids), but if you have GFO already, I'd use that.

I've had the GFO in for about a week now. I hadn't thought of testing the water coming out of the reactor, I'll do that later and see if it needs changed. I'll persevere with the rowaphos and keep this lanthanum in the cupboard for another couple of weeks.

I really need to get on top of this algae, between that and the aiptasia plague I'm dealing with I don't even like looking at the tank just now!

 

[Harris3005]

Lanthanum chloride works very well with combating high phosphates. Like any additive it has pros/cons. I have used it and have had great results, also does not require a reactor.

I've read a lot but I'm not sure if my phosphates are high enough to warrant using it. I don't want to cause problems by taking it too low. Some of the things I've read say that it should only be used for phosphates of 1ppm or above? I've got 10 grams of it here as a last resort if the rowaphos doesn't bring it down over the next couple of weeks.

 

[Halal Hotdog]

I've read a lot but I'm not sure if my phosphates are high enough to warrant using it. I don't want to cause problems by taking it too low. Some of the things I've read say that it should only be used for phosphates of 1ppm or above? I've got 10 grams of it here as a last resort if the rowaphos doesn't bring it down over the next couple of weeks.

You are correct with the need to be very careful with it. The dosage varies quite a bit depending on what brand Lanthanum you have and its dilution. Even if you have lower phosphates it can help, but can form more lanthanum carbonate than lanthanum phosphate. Watching your alk is very important. I no longer use GFO because of it. I don't dose all the time, and I keep my phosphate at the undetectable range on my Sailfert kit. I also have an ATS and a refugium.

 

[Harris3005]

You are correct with the need to be very careful with it. The dosage varies quite a bit depending on what brand Lanthanum you have and its dilution. Even if you have lower phosphates it can help, but can form more lanthanum carbonate than lanthanum phosphate. Watching your alk is very important. I no longer use GFO because of it. I don't dose all the time, and I keep my phosphate at the undetectable range on my Sailfert kit. I also have an ATS and a refugium.

Its 99.99% LaCl3 crystals that I bought from eBay that I have. I think I would need to use about 6.7 grams to get my phosphates down to 0.03. I don't have a 5 micron sock or a doser which I think I should probably get to use it properly?

 

[Halal Hotdog]

Its 99.99% LaCl3 crystals that I bought from eBay that I have. I think I would need to use about 6.7 grams to get my phosphates down to 0.03. I don't have a 5 micron sock or a doser which I think I should probably get to use it properly?

I agree that a 5-10 micron sock is important for catching the participate that forms. With that being said, I don't really use one anymore, I dose directly into my skimmer. The reason being is you will never catch all the participate that forms. Everything I have read indicates that the participate just settles and may never really disassociate again, unless there is a significant drop in Ph. The other issue with the participate is it can possibly get caught in the gills of some fish. I have not experienced this, but people have seen issues in tangs after dosing. The more participate you catch and remove the better.

 

[Greenstreet.1]

I used it to get my po4 down also I was using 6drops a day 3 in the sock and the other 3 in the skimmer. In used phosphate Rx I no longer use it as i run rowa po4 stays around 0.03 it gets lower if I increase the tumble of the rowa.

 

[griff500]

It's worth checking with a different test kit or checking your Hanna using a suitable reference solution (not the Hanna one) before taking action based on the results you are getting.

Did you test your effluent?

Has your algae not reduced in those 4 weeks?

 

[Colin_S]

i have almost the exact same problem with the same set up, my phospahte levels were 0.6, i managed to get them to drop 0.07 now back up to 0.13. i used Phosphate Ex to lower the PO4 but it does lower your alk. i also had a bad outbreak of red slime, could not get rid of it untill i does with chemi-clean, and that worked a treat, however it has sent my skimmer into meltdown, so waiting on that to calm down.
So my 2 cent is, dose with chemi clean, that will solve one problem, phosphate Ex is good ,be aware of your alk, but if like me, i still dont know the root cause so if you figure it out, keep us posted.. good luck

 

[deadreply]

Any update on the problem ?

 

[Harris3005]

Any update on the problem ?

Yeah I’m finally on top of them. No cyano or algae in the tank at all now. Just stopped kidding myself that I could skip water changes and stopped relying on phosphate removers and other quick fixes. For the first time since I set this tank up I’m really happy with it and I don’t feel like pulling my hair out when I look at it anymore!

There really is no substitute for time to let the tank mature and good maintenance and water changes!

 

[DesertReefBoy]

I used to use rowa all the time due to having high Po4. I found out the food I was feeding was adding Po4 to my tank. If I took rowa offline even for a few days my Po4 would increase to over 0.1 ppm. I really don’t like using rowa due to not being able to control the drop in Po4 very well. Maybe I was doing something wrong but it seemed as if Po4 would drop to sometimes zero and slowly start to climb. Eventually I ended up with dinos and after dealing with Dino off and on for 6 months tore the tank down.

I am now setting up a 90 gallon SPS dominate tank following the BRS WWC hybrid. I cycled the rock in a brute can for four months and then put the rock in the DT. After letting things settle for a month with weekly water changes my Po4 read 0.3 ppm. Not sure why it was so high. I was and am currently feeding LRS frozen food. I used Brightwells PhosphateE and SLOWLY brought the Po4 down. I was able to fine tune the dose and found out 1ml of po4E lowered Po4 roughly 0.1 ppm. I dosed the Po4E into the same chamber as the skimmer. I have three tangs (hippo, yellow and blue kole eye) and they have never shown any signs of stress. I have noticed white rock like pieces on the bare tank bottom after dosing sometimes. I even noticed the tangs pick at it and then swim off. I just suction it out when doing a water change. I don’t think I will ever go back to rowa to be honest. Sorry for the long post.