Help -- Sudden phosphate spike, O2 drop and algae explosion

[splunty]

TL;DR - in about 5 days massive algae explosion, ALK dropping, oxygen dropping, phosphates through the roof. Added GFO & increased O2 source. Anything else?

14g nano is about 4.5 months old, started with dry rock, bare bottom. Cycling took over a month, but finished very clean with no algae. Added 2 juvi clowns.

A few weeks ago my tank had it's first outbreak of diatoms. Added 3 nerite snails that maintained it well.

The tank gets a 2.5 gallon water change weekly as well as a good cleaning (it's a bare bottom, you know). There is no visible waste or old food, and I blow out the inside of the rocks during water changes. Filter changes twice a week, and usually twice with the water change.

This week, two things happend. The water chemistry had sudden swings in oxygen (down), ALK (down), and phosphates (skyrocket). These are my last 9 weeks, with the most recent week last:

Ammonia: .05, .05, .05, .05, .05, .05, 0, 0
Nitrite: 0, 0, 0, 0, 0, 0, 0, 0, 0
Nitrate: 5, 5, 5, 5, 10, 5, 2, 0
Phosphate: .03, .03, .03, .03, .5, .35, .35, 1.0 !!!
Calcium: 200, 200, 240, 300, 320, 360, 360, 375, 375
ALK: 8, 8.3, 8, 8.3, 8.3, 8, 8.3, 9.6, 7.7
pH: 8.15, 8.15, 8.15, 8.15, 8.15, 8.3, 8.15, 8.,15
Oxygen: 6, 6, 6, 8, 8, 8, 8, 4
Magnesium: (just got test kit) 1230, 1320
Salinity: 1.025 always

(edit: Tested phosphates/oxygen/alk twice with Salifert only. Confirmed nitrate with multiple tests as undetectable.)

Until last week, there was only a bit of green and light green algae here and there. This is a picture from this morning.

The camera simply won't pick up the colors, but there is:

Brown algae that is exclusively on the tips of the rocks in all light.
Thick green algae that is exclusively on smoother surfaces in generally lower light, and on the bare bottom.
Cyano only in the one corner where there is poor flow.
Dark maroon algae that can be brushed off with significant force.
Purple-pink super hard algae in tiny spots (this appears to be coralline). I actually can't remove it at all, even scraping.
Black algae/fungus that cleans off very easily with baster/suction.
Yellowish/green algae that can be brushed off easily but can't blow off with baster.

And then the worst... this is under exclusively very low blue light. Is this the beginning of bubble algae? I can't see it during the day at all. The "bubbles" were under a millimeter in size. I couldn't find them when cleaning today, so God help me if I caused a spore explosion.

And lastly, the hard growth that I believe is coralline is starting to die. Under the blue light a few specs of it glow a bright orange-red. Again, the camera doesn't pick this up, but it's very bright and I would guess luminescent. This was again last night... that spec was the largest in the tank (nerite for scale) and was glowing enough to spot from 10 feet away. This morning the spot no longer glows, but a couple of other tiny specs near it glow.

My primary concern is the phosphate spike, but I am curious how there's been such a sudden explosion in random algae so fast.

I added GFO after the water change this morning and scrubbed the algae out as much as I could.

1) Should I just wait out another week to see what phosphates do?
2) Should I change GFO every couple of days until it drops?
3) Should I increase the CuC (2 nerites, lol) or just keep cleaning?
4) How the heck did the O2 drop so fast?

Regarding oxygen: There's already probably too much surface agitation, and I was previously running my skimmer normally. This morning I moved the heater into the display so I could increase the waterfall drop in the AIO for more surface agitation, and removed the cup from the skimmer for more oxygen.

The clowns seem healthy, but I am starting to worry anyway. Help?

 

[Dan_P]

TL;DR - in about 5 days massive algae explosion, ALK dropping, oxygen dropping, phosphates through the roof. Added GFO & increased O2 source. Anything else?

14g nano is about 4.5 months old, started with dry rock, bare bottom. Cycling took over a month, but finished very clean with no algae. Added 2 juvi clowns.

A few weeks ago my tank had it's first outbreak of diatoms. Added 3 nerite snails that maintained it well.

The tank gets a 2.5 gallon water change weekly as well as a good cleaning (it's a bare bottom, you know). There is no visible waste or old food, and I blow out the inside of the rocks during water changes. Filter changes twice a week, and usually twice with the water change.

This week, two things happend. The water chemistry had sudden swings in oxygen (down), ALK (down), and phosphates (skyrocket). These are my last 9 weeks, with the most recent week last:

Ammonia: .05, .05, .05, .05, .05, .05, 0, 0
Nitrite: 0, 0, 0, 0, 0, 0, 0, 0, 0
Nitrate: 5, 5, 5, 5, 10, 5, 2, 0
Phosphate: .03, .03, .03, .03, .5, .35, .35, 1.0 !!!
Calcium: 200, 200, 240, 300, 320, 360, 360, 375, 375
ALK: 8, 8.3, 8, 8.3, 8.3, 8, 8.3, 9.6, 7.7
pH: 8.15, 8.15, 8.15, 8.15, 8.15, 8.3, 8.15, 8.,15
Oxygen: 6, 6, 6, 8, 8, 8, 8, 4
Magnesium: (just got test kit) 1230, 1320
Salinity: 1.025 always

(edit: Tested phosphates/oxygen/alk twice with Salifert only. Confirmed nitrate with multiple tests as undetectable.)

Until last week, there was only a bit of green and light green algae here and there. This is a picture from this morning.

The camera simply won't pick up the colors, but there is:

Brown algae that is exclusively on the tips of the rocks in all light.
Thick green algae that is exclusively on smoother surfaces in generally lower light, and on the bare bottom.
Cyano only in the one corner where there is poor flow.
Dark maroon algae that can be brushed off with significant force.
Purple-pink super hard algae in tiny spots (this appears to be coralline). I actually can't remove it at all, even scraping.
Black algae/fungus that cleans off very easily with baster/suction.
Yellowish/green algae that can be brushed off easily but can't blow off with baster.

And then the worst... this is under exclusively very low blue light. Is this the beginning of bubble algae? I can't see it during the day at all. The "bubbles" were under a millimeter in size. I couldn't find them when cleaning today, so God help me if I caused a spore explosion.

And lastly, the hard growth that I believe is coralline is starting to die. Under the blue light a few specs of it glow a bright orange-red. Again, the camera doesn't pick this up, but it's very bright and I would guess luminescent. This was again last night... that spec was the largest in the tank (nerite for scale) and was glowing enough to spot from 10 feet away. This morning the spot no longer glows, but a couple of other tiny specs near it glow.

My primary concern is the phosphate spike, but I am curious how there's been such a sudden explosion in random algae so fast.

I added GFO after the water change this morning and scrubbed the algae out as much as I could.

1) Should I just wait out another week to see what phosphates do?
2) Should I change GFO every couple of days until it drops?
3) Should I increase the CuC (2 nerites, lol) or just keep cleaning?
4) How the heck did the O2 drop so fast?

Regarding oxygen: There's already probably too much surface agitation, and I was previously running my skimmer normally. This morning I moved the heater into the display so I could increase the waterfall drop in the AIO for more surface agitation, and removed the cup from the skimmer for more oxygen.

The clowns seem healthy, but I am starting to worry anyway. Help?

Everything you describe kinda sounds normal for a new aquarium.

It is rare for an aquarist to track oxygen. There is little information on how it trends. I would expect it to decline at night and be hoghest during the day. A large decline could be a bacteria bloom, but I put that idea on the back burner and have you run the test one or two times more to confirm the results, once in the morning before or just after the lights come on and once in the evening before the light turn off.

 

[splunty]

Everything you describe kinda sounds normal for a new aquarium.

It is rare for an aquarist to track oxygen. There is little information on how it trends. I would expect it to decline at night and be hoghest during the day. A large decline could be a bacteria bloom, but I put that idea on the back burner and have you run the test one or two times more to confirm the results, once in the morning before or just after the lights come on and once in the evening before the light turn off.

Thank you for the kind reply. As somebody new to the hobby with nobody to talk shop with easily (my LFS is in the next town over) a bit of reassurance helps calm the nerves.

I'll test again tomorrow for phosphates and O2 and see if they've budged!

 

[splunty]

It's been about 36 hours since I added the GFO. Phosphates continue to rise to about 1.5 now (the Salifert test isn't precise). Oxygen is back up. The (no longer just suspected) bubble algae is exploding, and I am still unsure where it came from unless it piggybacked on the snails.

Both snails and clowns still appear healty. I really don't feel like I'm overfeeding, and I am spot feeding the fish. I don't think more than 1-2 pieces have hit the bottom in weeks.

Is it possible that enough algae is dying off to cause the phosphate spike? Is the tank too young to add an emerald crab to start attacking the bubble algae?

 

[Dan_P]

It's been about 36 hours since I added the GFO. Phosphates continue to rise to about 1.5 now (the Salifert test isn't precise). Oxygen is back up. The (no longer just suspected) bubble algae is exploding, and I am still unsure where it came from unless it piggybacked on the snails.

Both snails and clowns still appear healty. I really don't feel like I'm overfeeding, and I am spot feeding the fish. I don't think more than 1-2 pieces have hit the bottom in weeks.

Is it possible that enough algae is dying off to cause the phosphate spike? Is the tank too young to add an emerald crab to start attacking the bubble algae?

Everything growing in your aquarium came in with the livestock. No mystery there.

If there is enough bubble algae for the crab to eat, sure get a crab. Keep in mind that once the algae is gone, what does it get enough to eat.

How is the GFO being exposed to the aquarium water, a mesh bag? Are the rocks natural aragonite?

 

[splunty]

Everything growing in your aquarium came in with the livestock. No mystery there.

If there is enough bubble algae for the crab to eat, sure get a crab. Keep in mind that once the algae is gone, what does it get enough to eat.

How is the GFO being exposed to the aquarium water, a mesh bag? Are the rocks natural aragonite?

Thanks for the help, Dan.

The GFO is in a mesh bag. This is a 14 gallon AIO, and the bag is under the filter in chamber one.

The rocks are MarcoRocks Reef Saver. Their website states it is, "calcium carbonate rock," but there doesn't seem to be any breakdown or analysis.

 

[Dan_P]

Thanks for the help, Dan.

The GFO is in a mesh bag. This is a 14 gallon AIO, and the bag is under the filter in chamber one.

The rocks are MarcoRocks Reef Saver. Their website states it is, "calcium carbonate rock," but there doesn't seem to be any breakdown or analysis.

A couple thoughts about GFO. Firstly, this is not the most effective way to deploy GFO, but it can work, just more slowly. Be aware that it can be used up quickly. Is there some way to sample the water downstream from the mesh bag so that you can see a decreased phosphate level in the water before it reenters the aquarium? This is an easy way to determine when the GFO is used up.

I have seen comments about artificial rocks giving off or leaching phosphate. I don’t know if this applies to MacroRocks, but keep it in mind if you are considering starving the fish to bring down the phosphate level

 

[splunty]

A couple thoughts about GFO. Firstly, this is not the most effective way to deploy GFO, but it can work, just more slowly. Be aware that it can be used up quickly. Is there some way to sample the water downstream from the mesh bag so that you can see a decreased phosphate level in the water before it reenters the aquarium? This is an easy way to determine when the GFO is used up.

I have seen comments about artificial rocks giving off or leaching phosphate. I don’t know if this applies to MacroRocks, but keep it in mind if you are considering starving the fish to bring down the phosphate level

That makes sense. I hadn't thought of testing both before and after the GFO chamber, and yes that is something that could easily be done. Unfortunately, the phosphates number is at the top of the Salifert scale and I think trying that right now with the test I have isn't going to work... at least until the numbers come down a bit.

I think given what you have said that the best course of action is to change the GFO frequently at least until I see some movement out of the "dark blue" on the chart.

The Marco Rocks Reef Saver product was supposed to be natural: "All natural calcium carbonate rock that was once part of a ancient reef. Never any chemicals or additives. Often, you can spot fossilized ancient corals in the rocks." They farm it from a quarry in Florida. The idea that something in that rock is leaching phosphates (and who knows what else) makes sense.

The patience required in this hobby is going to drive me crazy. Thank you again. I have a plan now which is to cycle GFO and ... wait.

 

[splunty]

Back to normal, but I'm not sure how.

Over the next 4 days, changing GFO daily in my media basket, 1.0 -> 1.5 -> 1.5 -> 1.0 and I decided to cut the GFO in half and let the phosphate numbers drop back down to normal slowly since they seem to have topped out.

Then a thing happened.

I replaced my stock IM media basket with one from inTank hoping to solve the problem of dirty water leaching around the oddly poorly fitting IM basket into the middle and return chamber.

I moved the bio balls from the media basket into the return chamber as a bit of an experiment, and to free up the bottom chamber for activated carbon.

I absolutely forgot to put the GFO into the media basket, so I wound up just laying the bag on top of the filter in chamber one.

That night (about 10 hours later) I tested phosphates again and they were down below .03, barely detectable.

Repeated the tests, even with double reagents. Barely detectable.

I have removed the GFO and will continue to test daily. Luckily, livestock seems alright.

And the inTank media basket is a fantastic upgrade. No water leaching around, more room for media, and definitely cooler logo.