Diatoms

[bigcheed]

I'm having diatom problems in my 7.5g beta tank. This tank used to be home to my crystal red shrimp. But the pH crashed and I lost them all. I cleaned out the tank and replaced all the live plants with silk and added a log ornament and it became home to my betta who didn't like sharing a 10g with some Cory's. Since then the pH will not stay neutral and drops to 6 within a day. It comes out of the tap at 7. And diatoms is covering everything. All other water values are fine amnia 0 nitrite 0 nitrate 5ppm. Its beginning to do my but in. Any ideas folks ?

 

[Byron]

I assume this is a new set-up, meaning within the past couple of months?  Diatoms is a common issue in new tanks, due to the fluctuating conditions.  Once the biology settles, this should stop.
 
I should check to make sure this really is diatoms and not a form of brush algae which many take for the same.  If it easily comes off with your finger, it is diatoms.
 
On the pH, let it alone.  You have soft water fish so this is not going to cause the Betta any harm, quite the opposite.  The pH is connected to the GH (general hardness) and KH (carbonate hardness or Alkalinity).  These tend to buffer the pH, depending upon their respective levels.  The acidification of any aquarium is normal, and governed largely by the GH/KH along with water changes and substrate cleaning.  Live plants and fish load obviously impact it too, as would the presence of calcareous substances.  As I said, with soft water fish this is not likely to cause issues.
 
BTW, when testing tap water for pH, you need to out-gas the CO2 which if present will affect the result of the test as CO2 creates carbonic acid which lowers pH.  This is the same process as what occurs in the aquarium itself, though for different reasons.  You can let some tap water sit 24 hours before testing, or more quickly shake some very briskly in a covered jar for several minutes and then test.  The GH and KH you can ascertain from your water supply folks, probably on their website; worth knowing these numbers so you will better understand what is happening.
 
Byron.

 

[bigcheed]

once again thanks for the feedback byron. this tank has been set up for well over two years. its definatley diatoms its really easy to wipe off. its just a pain having to keep cleaning the tank out. with regards to the ph being low it just puzzles me why it dropped so suddenly and then stayed low. i thought at first it was all the plants and drift wood that had somehow caused the shift because the water stayed pretty neutral for a long time. my other two tanks have never had any of these issues allthough they are bigger. ive tried snails in this tank to no avail they die off in short order. im thinking this is due to the low ph. as for the gh/kh our local water is quite soft. gh 5 kh 4.

 

[Byron]

once again thanks for the feedback byron. this tank has been set up for well over two years. its definatley diatoms its really easy to wipe off. its just a pain having to keep cleaning the tank out. with regards to the ph being low it just puzzles me why it dropped so suddenly and then stayed low. i thought at first it was all the plants and drift wood that had somehow caused the shift because the water stayed pretty neutral for a long time. my other two tanks have never had any of these issues allthough they are bigger. ive tried snails in this tank to no avail they die off in short order. im thinking this is due to the low ph. as for the gh/kh our local water is quite soft. gh 5 kh 4.

 
I had assumed from your intial post that you recently re-set this tank, hence it was "new."  Regardless, having removed the live plants you now have nothing to take up nutrients, so algae will occur.  Diatoms in this situation are the result of low light and/or silicates (a mineral) in the water.  If there is a Betta, I would add some live floating plants.  Betta really need floating plants as they naturally cruise among them, and this would easily handle the nutrients.
 
As I said, the pH lowering is natural, due to organics.  Various factors affect this, and every tank is different.  I have seven tanks, and the pH varies among them due to the biological individuality, notwithstanding the same water, additives, fish loads, etc.  It is much safer and easier to let it do what it wants and stock accordingly, and the Betta will have no issues in soft acidic water.
 
On snails, Malaysian Livebearing Snails will do fine in soft water.  This is the best snail for any aquarium, as it gets everywhere including throughout the substrate.
 
Byron.