Phosphate high, 0 nitrate, what should I do?

[mfield16]

My plan of action appears to be working well. I have stayed on top of trimming the chaeto, replaced the phosguard weekly, removed half the sand, and I also reduced the light cycle to 10 hours (was 12).

 

I didn't add a fish, and I only feed 2-3 times a week now. After a month the PO4 has dropped to somewhere between .03 and .1, but it is so hard to tell with the Salifert color chart.

 

Now if I could only get my alk and calc to level out

[jedimasterben]

Hey, one step at a time!

 

Glad to hear it's starting to all work out!

[Adrnalnrsh]

My plan of action appears to be working well. I have stayed on top of trimming the chaeto, replaced the phosguard weekly, removed half the sand, and I also reduced the light cycle to 10 hours (was 12).

 

I didn't add a fish, and I only feed 2-3 times a week now. After a month the PO4 has dropped to somewhere between .03 and .1, but it is so hard to tell with the Salifert color chart.

 

Now if I could only get my alk and calc to level out

 

Good work!

 

The problem with frequent feeding is not enough food being eaten therefore a spike in phosphates.

 

I lowered my lights as well down to 8 hours from 10-11 hours and that helped me as well.

[duganderson]

Interesting thread. Can someone recommend a good thread or article talking about the following concepts in aquarium applications.........

 

"Recommended PO4 and NO3 levels are .02 and .2. Bacteria that consumes phosphates and nitrates need carbon to do so in a ratio of C:N:P = 106:16:1"

 

Also, any recommended reading about "bio pellets" and "bio reactors".

 

Thanks

[Adrnalnrsh]

Interesting thread. Can someone recommend a good thread or article talking about the following concepts in aquarium applications.........

 

"Recommended PO4 and NO3 levels are .02 and .2. Bacteria that consumes phosphates and nitrates need carbon to do so in a ratio of C:N:P = 106:16:1"

 

Also, any recommended reading about "bio pellets" and "bio reactors".

 

Thanks

 

Search on redfield ratios. I think Randy Holmes's site state phosphates should be ~.02 and Nitrats ~.2.

 

I would only recommend biopellets if you have high nitrates.

[jedimasterben]

There are times when the Redfield ratios don't apply and can lead to things like this.

 

 

 

 

Alllllllllllgae scrubber.

[duganderson]

Search on redfield ratios. I think Randy Holmes's site state phosphates should be ~.02 and Nitrats ~.2.

 

Stupid beginner type question....when folks say .02 for recommended phosphate levels do they mean .2 ppm or 2 ppm or does that really mean .02 ppm.

 

My api test kit only reads 0 ppm and 5 ppm for the first two levels. I'm sure this is one of the reasons folks don't like it.

[jedimasterben]

They mean .02. The API test you have isn't useful for a reef as it doesn't test accurately enough.

I don't think there's anything on the planet that I could agree with more.

[mcarroll]

Alrighty then. So nix the sponge filters, get some floss, ...

In my experience, mechanical filtration has little place in a reef. Ditch it altogether - you won't miss it.

 

Also remember that creeping PO4 means you are overstocked, overfeeding, and/or underutilizing water changes as a nutrient export mechanism.

 

You can try to bandaid it as suggested elsewhere, but you can also do what it takes to bring those three factors into balance and the PO4 will fall. (Keep it simple, I say.)

 

-Matt

[mfield16]

In my experience, mechanical filtration has little place in a reef. Ditch it altogether - you won't miss it.

 

Also remember that creeping PO4 means you are overstocked, overfeeding, and/or underutilizing water changes as a nutrient export mechanism.

 

You can try to bandaid it as suggested elsewhere, but you can also do what it takes to bring those three factors into balance and the PO4 will fall. (Keep it simple, I say.)

 

-Matt

I'm sticking with mechanical filtration because I still have small particulates floating through the water column without it. It doesn't completely solve that issue, but it is certainly much better. Why does it have no place in a reef?

 

I also determined that the elevated PO4 was caused by leaching from rocks and possibly the deeper sand bed. I don't think I am overstocked, I certainly do not overfeed, and I perform 20% weekly changes. So far just using Phosguard and switching it out weekly has significantly dropped the PO4. It is now .03 and steady. I plan on running it for a few months this way and then taking it slowly out to determine if the leaching has subsided.

 

So far so good, right?

[mcarroll]

 

I'm sticking with mechanical filtration because I still have small particulates floating through the water column without it. It doesn't completely solve that issue, but it is certainly much better. Why does it have no place in a reef?

[...]

 

First of all, I call those little particles "coral food". Why deprive your little "sea of mouths"? And....why is there so much particulate in the water to begin with? (i.e. its source) If it were "bad" I think I'd be tempted to try some Yellow Polyps as my "mechanical filter".

 

But you're the one asking, so...

 

To each their own: What I always tell people who want to consider mechanically filtering their reef is that if you can commit to "religious cleanings" - which means clean as soon as its dirty...weekly or more often in many cases - then yes, mech. filtration can be useful in some situations and not be the cause of any problems. (Pays to be very realistic about this.)

 

That said, mechanical filtration has very arguable negative effects in a reef and few convincing positives to recommend its use, IMO.

 

For one: Do you know how many algae fields have been caused by the mere presence of under-maintained mechanical filtration? (Many!) That is to say, algae disappears from the system when the mech. filter is removed but with no other husbandry changes... Other than "something extra for the aquarist to do" what good, in a reef, was it serving in the first place?

 

You did mention a "deeper sand bed" which thanks to gravity is ultimately another form of mechanical filter. I don't recommend more than "enough sand to cover the bottom" for the same reason (risk vs benefit).

 

But, in the event of deep sand...using a well-placed, well-maintained mechanical filter to help keep the sandbed from getting clogged with detritus* would actually be good I think. (Worst case: A little algae is a lot easier to rectify than a "ruined" sandbed.)

 

-Matt

 

* Typical in year 3-4 in a lot of reefs with a sandbed of more than an inch or so...sometimes sooner in less ideal situations.

[mfield16]

I will certainly do some more research on the topic. I an very interested to see what else I can find. I no longer have a deep sand bed for the reasons you stated.

 

This is the first I have ever heard of mechanical filtration seen as a negative, but I am still very new too the saltwater scene... May I ask what filtration you have going on your tank Matt? How about people with sumps? Don't most use filter socks?

[mfield16]

If I don't run mechanical filtration, or a skimmer, will that be fine? Would it be beneficial to add carbon?

[jedimasterben]

If I don't run mechanical filtration, or a skimmer, will that be fine? Would it be beneficial to add carbon?

Yep. I would look up what carbon does though.

[xerophyte_nyc]

A deep sand bed can work, but it takes a lot of effort so it may or may not be worth it. A DSB can reduce nitrates, but there are other ways to reduce nitrate including adequate bacteria on live rock. I employ a DSB not only for the nitrate reduction, but also because of the biodiversity it adds, along with a natural food source in the water column.

 

The problem with phosphates is that in the vast majority of tanks there has to be some sort of export, be it algae, Xenia or media. Plain and simple. If import > export, you will see the symptoms.

 

I agree about mechanical filtration, which deprives the tank of many benefits. Seems like the use of media works for you. Just stay in top of it and you will be OK.

[mfield16]

I am going to take the floss out. Seems that everything I read on the topic (just about every reef topic it seems) has conflicting points of view. The idea that the floss is removing "coral food" is what helped me make the decision.

I also quickly read up on carbon in nano tanks; Yet another widely debated topic for sure. What I pulled from that search is that carbon is useful for water polishing and keeping softies from killing each other in toxic warfare, but really isn't needed otherwise. A lot of carbon brands can also leach PO4 back into the tank, which is the exact opposite reason I started this thread. There have also been stories on the sudden addition of GAC that have caused problems to an otherwise stable tank.

So rather than change too much with my tank at one time, I am going to see how it reacts to no mechanical filtration at all. Depending on that, I may run carbon. Of course I will run a test to see if the brand I have sitting around leaches PO4. Who knows, I may be forced to add it since I have a frogspawn, a torch, and a leather coral crammed in a 15g tank...