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Diatoms - My "FACTS"

NC10

NC10

Member
Joined
20 Nov 2013
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566
Location
Sheffield
First off, mine is a newish setup so I expected some. It's not really a big issue from my point of view, but just looked into it a bit more today, see what I could do. More unsightly than anything really.

Anyway, ended up at blaming silicates and salicylic acid so did a quick google search for some media to remove it. I came across a link to a thread on UKAPS, so obviously read it. It's an old thread which is why I didn't bump it and started this, it featured Ceg anyway. Would be interesting to know his current view on them though. I noticed a few other threads in here as well which didn't fit in with my situation so thought I'd start this.

Feel free to post your actual facts and experiences, not just what you think or have been told, hopefully it could help a few people out.


My actual factual facts :p

1 - Tank is 2 months old. Some should be expected really, ride it out :D

2 - I read a thread about purigen. I've been running purigen a while due to excessive tannins and it's had no effect on diatoms. Would it have been worse without the purigen? I can't answer that.

3 - The only place I have a problem with them is in the LOW light areas of the tank. PROVEN now I have added an extra 54w and they're slowly but surely subsiding. I originally had 2 x 39 watt T5's towards the front of the tank and in a 4ft tank they didn't reach either end. I also have 2 huge chunks of wood which further block the light towards the back. Basically, only the front 50% was directly lit and maybe a 10" gap either side wasn't lit. I've now added the extra full length 54w in the middle where one of the 39w was and moved the 39w to the back behind the wood. The back glass and plants behind the wood are quickly clearing up since I've done this.

4 - I went up to over 29.5 degrees on one night and woke up the next morning to find the diatoms on the back wall had reduced to near enough nothing. They slowly reappeared as I dropped the temp. I haven't managed to find an answer on their optimum temperature, but maybe this was slightly too high for them.

5 - Main problem area is/was directly above a spraybar kicking out near enough 2000lph, so high flow isn't a problem for them.

Edit: In fact thinking about it, I don't really have as much of a problem on the back left hand side of the tank. The size of the pump and the distance before anything actually comes out of the spraybar means I don't have an aggressive flow until just before the wood on the left, which is where the diatoms start. This would leave me to believe they actually prefer more flow.

6 - Until I actually wrote fact 1, I didn't realise how young my tank was. I won't be rushing out to find a quick fix just yet :D
 
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Whatever anyone tells you, diatoms feed on silicates. That is a simple fact. In all seawater on the planet, the more silicates there are, the more diatoms are present. It's only reasonable to apply the same logic to our tanks.
 
Also, I mentioned the fact that diatoms occur mostly in low- light environments. I was basically told I was stupid and that my experience was invalid.

Oh well, doesn't matter really.

All I know is that diatoms are brown. Chlorophyll is green. I'll let you work out the rest.
 
Got rid of the diatoms in my main tank by removing the sand (not the reason for removing the sand).

Shrimp tank has them everywhere but no sand.

Replacement planted wall shrimp tank only receiving reflected light from main tank, currently void of livestock except beneficial bacteria and the odd cyclops, no sand but lots of aquarium silicone, zero diatoms.

Conclusion - I over feed my shrimp tank!

:)
 
I dont have any 'facts' to offer up to you but i will be devils advocate....

new Fowlr marine tanks also get diatoms at start up without sand, i think its also logical to assume that as sand is white and diatoms brown people assume there are more of them and link the two, blaming silicates. Not to mention that plenty of people change there sand in mature marines and dont suddenly get diatoms again.

Diatoms appear in most new tanks, with sand, without, high light, low light... its how you deal with them that matters.

Is it not possible that you added the extra light as time went on meaning the diatoms were starting to come to an end also??

Low light areas of our tanks are also normally the low flow areas, diatoms within the water column will naturally settle in low flow areas giving a misconception.

Like i said, i have no facts. Unless we do any of these things in a controlled situation then its speculation, ive had terrible diatoms in my low light shrimp tanks but none at all in asian dreams high light with sand, loads in barb island high tech high light no sand... who knows, certainly not me.

Sacha said:
It's only reasonable to apply the same logic to our tanks.
Click to expand...
whats reasonable and whats true are two entirely different things..... nearly every logical decision ive ever made with fish tanks have proven to be incorrect with experience. Just saying :)
 
Iain Sutherland said:
Is it not possible that you added the extra light as time went on meaning the diatoms were starting to come to an end also??.
Click to expand...

No they weren't coming to an end, they've been the same really all along with no change. I went a bit too high with the temp one night and the next day they'd drastically reduced, virtually diassapeared off the back wall, that's surely not a coincidence, they quickly returned as the temp got back down to more reasonable levels.

Like with the lights, all this is over the course of just a couple of days it's drastically reduced, not a few weeks like you would expect with it dying out naturally.

Iain Sutherland said:
Low light areas of our tanks are also normally the low flow areas, diatoms within the water column will naturally settle in low flow areas giving a misconception
Click to expand...

It's the highest flow area of the tank where the problems are. I have a spraybar mounted just above the substrate firing up the back wall. This was also the lowest lit area until I moved the 39w to the back. Now it's lit, the diatoms are disappearing. If they do have a preference, then they definitely prefer the higher flow.
 
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I use to have a big problem with Diantoms in my tank. I lowered the light, added more CO2, got spray bars, did a 4 day blackout ....nothing really helped...I ended up with 1x 54W tube 6 hours per day over a 300 ltr tank. Not much high tech in that!
Now I got rid of the spray bars (even lowered the pumps output for a while), much more light, but most of all a whole lot more plants and voila no more Diantoms.
Now just need to tackle those BBA, not much but still to much to me.
 
Well I'll tell you how I triggered diatoms in two tanks recently.

Tank 1. Pulled all the plants out of the tank, increased light to 12hrs-needed algae for an otocinclus fry. Tank is 2 years old.
Tank 2. Increased feeding from once to twice a day, added a whole lot of bioload as I moved all the shrimp from tank 1 to tank 2. This tank is 4-5 years old, hadn't seen algae in 4 years in it, very sparingly planted. I did not change light levels in it.
 
My experience of diatoms...

First version of tank: (lower light, high CO2, EI dosing)
Always there, never rid of it… terrible plant health and a mess

Current version of tank: (higher light, good CO2, EI dosing)
First bloom after about 2-3weeks after flooding dry start. Lasted until I put large amount of plant mass in and then slowly decreased as plants became healthier. Second bloom (all varieties of algae) after a mistake with CO2 resulted in melting plants. slowly decreased after everything came back to health.

Previous tanks:
Occupied with a single huge goldfish - very low light (Single T8), high bio-load, lots of half eaten plant stumps. Absolute diatom madness, great sheets of brown carpet on everything.

My very unscientific conclusion: caused by pollution/ammonia
 
Whenever I have diatoms, they spread upwards from the substrate. So they always originate from there.
 
Mr. Teapot said:
My very unscientific conclusion: caused by pollution/ammonia
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That's my opinion too. It can be conquered in any tank with healthy plants and good filtration as long as one isn't pushing the limits with stocking and overfeeding.

Sacha said:
Whenever I have diatoms, they spread upwards from the substrate. So they always originate from there.
Click to expand...

They actually appear at lower levels because of the lack of flow there. They don't seem to be able to latch on to surface subjected to higher flow. One of my tanks at the moment has a straight clear patch of about 5cm wide all around the tank glass near the surface area and that's because the surface movement is too strong for them there. It's a straight line cut as if I wiped it all above the line.
So it may appear to someone they grow from the bottom up because there are more at lower level.

I've had the two tank examples above for years, both with sand and both had no diatoms since I set them up first so there's no way I can blame the sand for the diatoms that decided to appear now. But I can cause it without a fail by increasing bioload and overfeeding.
 
NC10 said:
It's the highest flow area of the tank where the problems are. I have a spraybar mounted just above the substrate firing up the back wall. This was also the lowest lit area until I moved the 39w to the back. Now it's lit, the diatoms are disappearing. If they do have a preference, then they definitely prefer the higher flow.
Click to expand...

Are you sure this is diatoms and not brown algae? As science said diatoms are generally pretty free flowing and don't really attach anywhere until they hit plant mass like bunches of eleocharis or low flow areas then gather...

No idea about the temp bit but certainly worth investigating...



Sent from my iPhone using Tapatalk
 
Iain Sutherland said:
Are you sure this is diatoms and not brown algae?
Click to expand...

All the research I've done to find out what and why I had it, pointed at diatoms and/or brown algae. Most of the time the two being interchanged as though they were the same thing, both feeding on silicate and low light etc It's sort of dusty for want of a better word, which led me to diatoms. It's easily wiped of the back glass just by the leaves rubbing on it due to the flow.

Are they not the same thing? What's the difference?
 
My experiences with diatoms ..
They appear and go away with no extra effort on my part. (just time passing)
 
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