Black mold

I would personally take those ceramic "bio-filter" rings out of your filter and replace it with some filter floss.
You have rock in your tank to take care of your bio-load and you need all the filtration you can get your hands on!
Replace the floss often!

 

Thank

 

floss?

 

Ok. So after reading your response . And your lack of response to the question concerning what type of water are you topping off with would leave me to believe you using tap to top off with ? Yes?

If yes as mentioned befor your prolly getting a spike of phosphate or some other particulate that's causing your bloom .

If you are infact doing that . I can suggest a semi cheap way to get great water .

 

this is just my opinion, But I would personally use something like seachem chemi-pure elite instead of the floss. The filter in the pictures looks like its just a mechanical sponge. A protein skimmer and/or refugium would be a great upgrade for that tank as far as filtration goes. Are you in Europe? (doesnt matter, im just curious... I saw the euro symbol on the ebay pic). If you are infact using tap water (water out of your sink faucet) then I would HIGHLY recommend using cleaner water, such as distilled water, or reverse osmosis water for water changes and evaporation top offs. Tap water often contains phosphates which can fuel unwanted algae growth. Also, anytime you have a problem with your tank, frequent water changes (weekly or even more often) can sometimes be the best thing for your tank.

 

London, UK

 

3 stage aquarium reverse osmosis system unit marine discus fish? Black mold?

 

Normally RO/DI filters have 4-5 stages. 1 or 2 sediment filters, a carbon filter, RO membrane, then DI resin. A 3 stage probably does not have DI resin, which will still be better than what you have but you may not be able to get zero TDS (total dissolved solid) water.

As far as the second part of your question, Im not sure what you are asking. If you are asking if it will get rid of your black mold (which I believe is cyanobacteria) then I can tell you it is one of many steps in the right direction and will definitively help.

 

EASY LIFE BLUE EXIT 250 ML against Cyanobacteria blue green algae slime algae? Easy Life eXcital 250ml Red Slime Algae Cyanobacteria Marine Freshwater?

 

Band aid. As previously stated. You need to find the root of the problem. Nothing in this hobby is quick, including fixing things.