Nearly Constant Diatoms in an Established Tank

[sawdonkey]

My tank is nearly three years old and I consistently have diatoms. It's not devastating, but obviously I'd rather not have them. Every few days, they show up on my sand bed, mostly in lower flow areas. I use a shallow sand bed, so sometimes I just stir it up with a filter sock on my return, sometimes I use a gravel vac into a filter sock in my sump. This usually fixes the problem for a few days.

The diatoms are brown and dusty on a really only on my sand bed and glass.

Tank stats:
-220 gallon with 75 gallon sump
-big skimmer (Skimz SM201)
-Biopellet reactor
-GFO reactor
-Tons of flow. One Gyre, two Jebao RWs (15&20). I have a hard time keeping my gravel in place.
-All substrate and rock is at least three years old (except a couple of small pieces of live rock)
-I have some big fish so I feed big (Emperor, PBT, naso, Niger, Picaso, lemon peel, clown)
-Tank is SPS dominate and corals are doing well
-I have four OR T247s for light. 80% blue 40% white, 10 hours of blue, 6.5 hours of white. I had this diatom problem with my old lights too.
- I dose a little a dose power now and then
- I've tried dosing MB7 and it seems to have some positive impact, but led to a weird green cyano.
-Nitrates always run between 0-3 and PO4 is always between 0-.03

Any thoughts? I'm inclined to think it is Biopellet related, but I'm afraid to take them off-line because they do such a good job with NO3 reduction. In ideas or advice would be greatly appreciated.

 

[Marquiseo]

Raising the pH worked for me. I siphoned majority of it and raised the pH which now remains constant between 8.2 and 8.5. I have been diatom free for months.

 

[sawdonkey]

Raising the pH worked for me. I siphoned majority of it and raised the pH which now remains constant between 8.2 and 8.5. I have been diatom free for months.

I never test ph, but I maintain calcium and alk with kalk, so I imagine I don't have low Ph.

 

[brandon429]

After collecting several follow ups in our algae threads, you have a strong chance of control through uv, the offender is a non holdfast water transient for sure uv is contender

We never buy the right size uv for the tank


Off amazon, from a seller with a return policy online, we buy grossly oversized uvs for decent sized ponds.

We wield uv well in the big peroxide threads, they aren't all about p

In the nano reef.com p thread, we use fifty watts uv on a nano to tame ostreopsis dinos by grossly oversizing you can attack the colonial support and then take it offline, store in garage for next need.

Oversized uv is also unimpactful to try, all current methods are param alterations. The downside of you running grossly oversized uv on a 28 day evaluation purchase, is exceptionally clear water of high oxygenation and a gross reduction in invader to the point of not needing to run it. The uv isn't used to clean up the current biomass

It's added only after the most thorough, dirty sandbed exporting cleaning ever done to mass export the target first.

On top of gross wattage oversize, the biomass target is near totally reduced at first go. We do collect fixes of water transient invasions for sure. Quite possible to hit with a little peroxide for a boost at that time of bright light
Pro uv rant off

 

[sawdonkey]

After collecting several follow ups in our algae threads, you have a strong chance of control through uv, the offender is a non holdfast water transient for sure uv is contender

We never buy the right size uv for the tank


Off amazon, from a seller with a return policy online, we buy grossly oversized uvs for decent sized ponds.

We wield uv well in the big peroxide threads, they aren't all about p

In the nano reef.com p thread, we use fifty watts uv on a nano to tame ostreopsis dinos by grossly oversizing you can attack the colonial support and then take it offline, store in garage for next need.

Oversized uv is also unimpactful to try, all current methods are param alterations. The downside of you running grossly oversized uv on a 28 day evaluation purchase, is exceptionally clear water of high oxygenation and a gross reduction in invader to the point of not needing to run it. The uv isn't used to clean up the current biomass

It's added only after the most thorough, dirty sandbed exporting cleaning ever done to mass export the target first.

On top of gross wattage oversize, the biomass target is near totally reduced at first go. We do collect fixes of water transient invasions for sure. Quite possible to hit with a little peroxide for a boost at that time of bright light
Pro uv rant off

Thanks for the suggestion, but I'd really rather not incorporate another piece of equipment.

I know you're the pro-peroxide guy, but I dosed it a while back when I thought I had Dinos, and I didn't like the way my corals responded.

 

[saltyfilmfolks]

You said gravel on the sand bed. What substrate do ya have.
It sounds like you have a nutrient sink. Could be the sand or gravel bed or somewhere else.
The usual nook and cranny cleaning of course to find the source.
If there are none I'd look at the bio pellet reactor. I don't have a lot of experience with that media but I thoug that they do add nutrient or bacterial mass to the tank.
Perhaps slowly dial the reactor back and substitute Chato or something.
Dosing prime or stability I can recommend been fine to no change in my tank.

I personally don't like cross dosing. If your adding bacterial (bio pellets mb7 prime) you shouldn't dose others at the same time. Too many ingredients at the same time. Bacterial colonies fighting for space plus whatever is n the bottle to keep the bacteria alive(food). That could feed the other bacterial.

 

[sawdonkey]

You said gravel on the sand bed. What substrate do ya have.
It sounds like you have a nutrient sink. Could be the sand or gravel bed or somewhere else.
The usual nook and cranny cleaning of course to find the source.

Thanks for the suggestion. I use fine gravel, not sand. It's only an inch deep in most places. I don't know the brand, but it's three years old. I stir it thoroughly at least once per week. I also gravel vac it about every other week. I use a turkey baster on my rockwork. Occasionally, I use a power head to really blow everything out from under my rocks. There's very little detritus in my tank. I'm a clean freak and won't even let a tiny bit of coralline grow on my glass or overflows.

I'm pretty sure I don't have a nutrient problem.

 

[sawdonkey]

You said gravel on the sand bed. What substrate do ya have.
It sounds like you have a nutrient sink. Could be the sand or gravel bed or somewhere else.
The usual nook and cranny cleaning of course to find the source.
If there are none I'd look at the bio pellet reactor. I don't have a lot of experience with that media but I thoug that they do add nutrient or bacterial mass to the tank.
Perhaps slowly dial the reactor back and substitute Chato or something.
Dosing prime or stability I can recommend been fine to no change in my tank.

I personally don't like cross dosing. If your adding bacterial (bio pellets mb7 prime) you shouldn't dose others at the same time. Too many ingredients at the same time. Bacterial colonies fighting for space plus whatever is n the bottle to keep the bacteria alive(food). That could feed the other bacterial.

Yeah, I don't really dose MB7 regularly. It was just to try to address the diatom issue. MB7 is the bacteria, and bio pellets are food for the bacteria. I've used bio pellets for two years and really like them.

I used to use chaeto, but my PO4 crept up so I added GFO. With the GFO, the chaeto died. Maybe I'll go back to that method and only run GFO on an as needed basis.

 

[brandon429]

after eliminating all possible attack points, curious as to the direction that w be taken

do you have fts> wondering if the id is spot on/cyano wondering. it seems grazer selection is the only possible mode left of the suggested fixes, conchs and cowries w eat it sometimes.

 

[sawdonkey]

after eliminating all possible attack points, curious as to the direction that w be taken

do you have fts> wondering if the id is spot on/cyano wondering. it seems grazer selection is the only possible mode left of the suggested fixes, conchs and cowries w eat it sometimes.

I don't have a recent FTS, but here's my thread that should have one a few posts back. Nothing shows the diatoms, because i typically only break out the camera after a good cleaning. [emoji4]

Sawdonkey's 220 Progress Thread
https://www.reef2reef.com/index.php?threads/Sawdonkey's-220-Progress-Thread.162105/

I've got grazers. A naso tang, a powder blue, a fighting conch, and tons of hermits.

The diatoms are really dusty, so I'm pretty sure it's not cyano.

 

[Randy Holmes-Farley]

Diatoms usually burn out after the silicate runs out. When I dose it I can see a burst of diatoms that goes away.

They must have silicate to survive, and little else in your tanks does (except sponges). So tracking down the source (if the pest really are diatoms) can work.

How do you make top off water?

 

[sawdonkey]

Diatoms usually burn out after the silicate runs out. When I dose it I can see a burst of diatoms that goes away.

They must have silicate to survive, and little else in your tanks does (except sponges). So tracking down the source (if the pest really are diatoms) can work.

How do you make top off water?

I use a spectra pure 4 stage rodi. I'm probably due for a change of filters soon. I last changed my carbon block and pre filter in June. DI resin is still pink about half way. TDS meter says zero still. I ordered all three earlier today(Black Friday WooHoo!), so I'll change those early next week.

I do top off into a 25 gallon just and mix with kalk.

 

[NanaReefer]

What brand of substrate did you use?

 

[Randy Holmes-Farley]

I use a spectra pure 4 stage rodi. I'm probably due for a change of filters soon. I last changed my carbon block and pre filter in June. DI resin is still pink about half way. TDS meter says zero still. I ordered all three earlier today(Black Friday WooHoo!), so I'll change those early next week.

I do top off into a 25 gallon just and mix with kalk.

Ever measure the TDS of the RO/DI effluent?

Silicate can be among the weaker bound ions, and when the DI first depletes, can actually be higher in the effluent than in the tap water.

 

[Pfisherman]

Ever measure the TDS of the RO/DI effluent?

Silicate can be among the weaker bound ions, and when the DI first depletes, can actually be higher in the effluent than in the tap water.

I am with the good Dr on this one. The only time I get diatoms is when there are too high of silicates in my water. If you have a silicate test kit then there you go,otherwise don't do any water changes and watch them disappear. Sure its not cyano?

 

[Dtackett]

Ever measure the TDS of the RO/DI effluent?

whats that and how do I test it lol

 

[sawdonkey]

Ever measure the TDS of the RO/DI effluent?

Silicate can be among the weaker bound ions, and when the DI first depletes, can actually be higher in the effluent than in the tap water.

I'm not sure what your mean? By rodi effluent, do you mean my wastewater, or do you mean my clean water going into my tank? No, I've never measured my wastewater. The water going to my tank is @ zero.

Maybe you you could clarify? Thanks for your help by the way.

Is it possible that bio pellets could contain silicates?

 

[Randy Holmes-Farley]

whats that and how do I test it lol

It is a way to measure that the DI is not depleted. Color changing is not the best way.

These cover it:

Reverse Osmosis/Deionization Systems to Purify Tap Water for Reef Aquaria by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-05/rhf/index.htm

and

What is TDS? by Randy Holmes-Farley - Reefkeeping.com
http://www.reefkeeping.com/issues/2004-04/rhf/feature/index.htm

from the first one:

Monitor the DI resins by measuring the effluent’s conductivity, either with an inline meter (set to its most sensitive level), or by measuring the effluent manually. If you are using a TDS or conductivity meter, then the measured value should drop to near zero, or maybe 0-1 ppm TDS or 0-1 mS/cm. Higher values indicate that something is not functioning properly, or that the DI resin is becoming saturated and needs replacement. That does not necessarily mean, however, that 2 ppm TDS water is not OK to use. But beware that the flow of impurities and the conductivity may begin to rise fairly sharply when the resin becomes saturated. Do not agonize over 1 ppm versus zero ppm. While pure water has a TDS well below 1 ppm, uncertainties from carbon dioxide in the air (which gets into the water and ionizes to provide some conductivity; about 0.7 mS/cm for saturation with normal levels of CO2, possibly higher indoors) and the conductivity/TDS meter itself may yield results of 1 or 2 ppm even from totally pure water by not being exactly zeroed properly. Also note that the first impurities to leave the DI resin as it becomes saturated may be things that you are particularly concerned with (such as ammonia if your water supply uses chloramine or silica if there is a lot in the source water).

 

[Randy Holmes-Farley]

I'm not sure what your mean? By rodi effluent, do you mean my wastewater, or do you mean my clean water going into my tank? No, I've never measured my wastewater. The water going to my tank is @ zero.

Maybe you you could clarify? Thanks for your help by the way.

Is it possible that bio pellets could contain silicates?

The purified water. So it is 0 ppm TDS?

Biopellets shouldn't have silicate in them.

 

[Dtackett]

It is a way to measure that the DI is not depleted. Color changing is not the best way.

These cover it:

Reverse Osmosis/Deionization Systems to Purify Tap Water for Reef Aquaria by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-05/rhf/index.htm

and

What is TDS? by Randy Holmes-Farley - Reefkeeping.com
http://www.reefkeeping.com/issues/2004-04/rhf/feature/index.htm

from the first one:

Monitor the DI resins by measuring the effluent’s conductivity, either with an inline meter (set to its most sensitive level), or by measuring the effluent manually. If you are using a TDS or conductivity meter, then the measured value should drop to near zero, or maybe 0-1 ppm TDS or 0-1 mS/cm. Higher values indicate that something is not functioning properly, or that the DI resin is becoming saturated and needs replacement. That does not necessarily mean, however, that 2 ppm TDS water is not OK to use. But beware that the flow of impurities and the conductivity may begin to rise fairly sharply when the resin becomes saturated. Do not agonize over 1 ppm versus zero ppm. While pure water has a TDS well below 1 ppm, uncertainties from carbon dioxide in the air (which gets into the water and ionizes to provide some conductivity; about 0.7 mS/cm for saturation with normal levels of CO2, possibly higher indoors) and the conductivity/TDS meter itself may yield results of 1 or 2 ppm even from totally pure water by not being exactly zeroed properly. Also note that the first impurities to leave the DI resin as it becomes saturated may be things that you are particularly concerned with (such as ammonia if your water supply uses chloramine or silica if there is a lot in the source water).

oh, so its what my inline meter is measuring? wasn't sure what the effluent aspect of it was lol