lights and diatom

[xsdbs]

can lights cause a brown diatom layer on my sand and glass as the lights get older? my lights are only about 6 months old and I usually change them out @ about 8 months. Is this to long of an expectancy for my lights. oh yeah, they are HO 60 inch flourscents rated @ 110 watts. Thanks in advance for any information

[Amphiprion]

can lights cause a brown diatom layer on my sand and glass as the lights get older? my lights are only about 6 months old and I usually change them out @ about 8 months. Is this to long of an expectancy for my lights. oh yeah, they are HO 60 inch flourscents rated @ 110 watts. Thanks in advance for any information

Lighting isn't usually to blame. Extra silicates and phosphates are. I'd check the TDS and silicate/phosphate concentration in your source water/tank.

[xsdbs]

I am using city water and a little over a month ago the city sent out water test reports and the phos was way lower than the minimal accepted by the city. I am also using a coral life RO unit so I would think my water would be of decent quality. I will need to pick up a new test kit for phos and maybe add one of those phos pads to the sump. Thanks

[Amphiprion]

Also, do yourself a favor and buy a good TDS meter, which measures the Total Dissolved Solids of the product water (in other words, a fairly direct measure of purity). They aren't too expensive, either.

[xsdbs]

Thanks for the input, is there a particular tds unit I should look at?

[7faces]

Umm, I noticed in my post about sand, that you use white kiln dried sand from home depot...Silicates are the reason I dont use that stuff...it is 100% silica sand (should even say it on the bag, or ask for an MSDS), and is prone to leaching silicates..(i truethfully dont see how it CAN'T leach silicates)..
Im not the most expierienced in the hobby by far, but I'm guessing it may be the root of your problem?

[Amphiprion]

Well, it should leach them for a while, then it should taper off pretty sharply as the grains are coated with a biofilm. There may be enough solubility to be a problem though--not entirely sure.

[xsdbs]

the tank has been up for well over 1.5 yrs and this problem is one that just pops up once in a while. I had read other threads about this product and originally tried playsand but that made such a mess in the tank, had to run heavy on the filters for about a week even after I rinsed the stuff before putting it in the tank.

[Fishieness]

I am using city water and a little over a month ago the city sent out water test reports and the phos was way lower than the minimal accepted by the city.
That really doesn't mean anything. We can take pretty high concentrations pretty easily. But for our tanks, it should be pretty much AT 0. My guess is even if it is way below the accepted rate for human drinking, it is still way to high for your tank.
And the silica sand would also DEFINITELY help. It is possible that the random spurts are from something stirring up your sandbed. As the bacteria which is deep in the sand is exposed to oxygen in the water, it dies a would then have to be coated again.

[Amphiprion]

Definitely. I forgot what our city standard was (I think around 1 ppm), but it is well above what is recommended for aquaria.

[xsdbs]

ok, so to deal with my ignorance here on dsb. I see this stuff and I do either 1 of 2 things:
1) stir it ( I have just read that this is not good )
2) try to vac it up when doing water changes, only thing is that I insert the python tube into the sand and lift to let the heavier sand particles to drop back to the sand.
I am assuming these are both bad. I just got off the phone to have another water quality test report sent to me, should be here monday. If my memory is correct it was near 0.
I have 2 rio 2100 power heads and a korlia 4 inside the tank for additional circulation along with my mag 24 for return from my sump. The small problem with the rios is that the stream is so directional that I have to run it thru the rocks or they will blow the sand around. I have thought about taking a pvc tube and drill holes in it with a plugged end cap to run along the ends of the tank for better circulation, I am not sure about the size holes and how many. I don't want to restrict or lessen the flow.

[Amphiprion]

Actually, making a spraybar like you are mentioning will reduce flow and overall circulation. I would avoid spraybars for that very reason. Stick with the high volume pumps. I suppose you are referring to Rio's Seio pumps, correct? If not, try one of the higher volume, lower velocity powerheads, like from Hydor (Koralia), Seio, Tunze, and maxijet mods.

Edit: NM. I didn't read the full post, apparently. Anyway, I suggest replacing the Rio 2100 with another high volume powerhead. You should have less problems with the sand with that.

[xsdbs]

please excuse me if this is a dumb question.
the rio 2100 is supposed to be high output ( as told by the lfs ) how does a powerhead have high volume and lower velocity. I had thought of high output as water turbulence which would be movement. how does a different power head with high flow have less velocity, :confused:

[Amphiprion]

Ok, take a comparison of two powerheads--a Tunze stream and a maxijet. The Tunze, when measured, has a much lower outlet velocity compared to the maxijet. However, the Tunze also emits a much larger volume of water--in other words, even though it isn't shooting water molecules as "fast" as the maxijet, it is pushing many more water molecules. Hope that makes sense.

[xsdbs]

I think I got it, I have not really looked at the size difference of the output nozzle but could it also be compared to a garden hose, if you apply your thumb to the end to get a spray the volume of water is the same as without the thumb but has a more powerful stream? never really thought of it that way. hey thanks for the help.

[Amphiprion]

Actually, because of that, the volume would be reduced. Same principle behind those water-saving hose nozzles.

[Almondsaz]

So Amp...you are suggesting that like the treatment for cyano, increase the flow to deter the diatom bloom? MY phosphates are 0 and my nitrates are at about 20ppm and I am working to get them down lower (were as high as 40). I have good flow in my tank as it is-----what else could it be?

[Amphiprion]

So Amp...you are suggesting that like the treatment for cyano, increase the flow to deter the diatom bloom? MY phosphates are 0 and my nitrates are at about 20ppm and I am working to get them down lower (were as high as 40). I have good flow in my tank as it is-----what else could it be?

Not necessarily for that, just flow in general. I don't really recall what got me on the subject... In any case, the prevention of settled detritus will make a difference with most algae on the sandbed. Do you have a refugium? Are you using any sort of phosphate removers, etc.? Other than that, there isn't much beyond more complicated and/or expensive options (ie nitrate reactors and reductors). Then there always the organic carbon driven bacterial systems (zeo, prodibio, vodka, vinegar and sugar addition), though I don't particularly like these. As far as to why, there are too many factors that could be considered. It boils down to individual tank dynamics.

[xsdbs]

Actually, because of that, the volume would be reduced. Same principle behind those water-saving hose nozzles.
well ok I thought I had it down. I will just go check out some other units like you had suggested. Thanks

[Almondsaz]

Could it be the performance (or lack of) of the skimmer leading to the diatoms? One other item, is it possible that the use of the bio-wheel in a HOB filter is a contributor as well?

[Amphiprion]

The Bio-Wheel very well could be a contributor to nitrate levels, as would a skimmer with sub-par performance. As to exactly that causing your diatom problem, again, there are too many variables involved. I would think, though, that getting the nitrate down a bit won't hurt the situation.

[Almondsaz]

Thank you Amphiprion...I have removed the Marineland/dual biowheel filter. I will let the sump/fuge hopefully do their magic and test tomorrow for the nitrates. Appreciative of the advice.

[Amphiprion]

No problem. Hope that is the root cause for you. Try doing a water change, then test. Give it a week or so and test again to see if it has risen to its former level.