Diatom Question

[Seaslug]

Since starting my tank in January I've had repeated Diatom "blooms" with related die off. I can only assume they come from the water I add during water changes and top offs. The water is fom my shallow well and is chemically quite good. I currently have 3-blue chromis along with 3-snalis and 2-3 hermit crabs in the tank. Is there something I may do to stop the die off? I do 5+ gallon changes weekly made of water that I have heated and corrected for SG for at least a week before doing the changes. Any ideas greatly appreciated.

Here’s my set-up

50 gallon breeder tank
50+ pounds of cured live rock
50 pounds of sand
1-SQWD with a Mag 7.5 pump
1-Eheim 2236 canister filter (270 gph) with a coarse pad, 4 levels of substrate and a fine filter pad on the top using carbon
1-Remora C Skimmer with a Maxijet 1200 pump
1-Coralite 36" light with 1 10,000K and 1-Actinic for a total of 196 watts (running 8-10 hours per day)
5-snails (Astrea I believe)
2-Red leg hermits
3-blue leg hermits
3-blue reef chromis

My water parameters are as follows:

KH/Alk 10.9/3.89

CA 430 ppm

NH4+NH3 <.25 (essentially 0, this is the lowest reading on the scale of my test kit)

NO3 0-.2

pH 8.3

SG 1.024

Thanks for the help

 

[Max]

When you say die off you're talking about the algae right? When you change your water you're adding free silica it's triggering the diatom bloom untill it's all used up and most of it dies. The only way to stop this cycle is to somehow remove the silica from your water. You might be able to do so with a filter but I'd still reccomend r.o. water if you live in an agricultural area especially. This summer when the growing season starts you might find the nitrate/nitrite levels in your well water going up from run off .
hth
chris

 

[Seaslug]

Diatom "blooms"

maxilaria,
Thanks for the information. The shallow sand bed in my tank is silica based sand, not coral. Would it be helpful if I changed out my sand for coral sand? As you say the silica is in my water. Therefore an RO unit "may" help. Suggestions on an RO unit? I'll need approximately 6 gallons per week as this is my typical water change and provides for a gallon of top up water too. On the other hand unless the die off is damaging to the tank's inhabitants may I just live with it and let my clean-up crew do their job?

Thanks Again

 

[Max]

Sure you can live with it . It won't hurt anything unless it covers a coral etc. The silica in your sand isn't water soluble so don't worry about it. 6 gallons isn't much water at all you it may be cheaper to buy it. I have a still so someone else would need to advise you as far as r.o. goes. If you decide on a still get one that has either a ceramic element or stainless steel. I use a water wise with out the coco nut fiber filter.