what is this

[davescube]

i have been looking how phosphates crystal looks like in
aquarium.. but i cant really find it.. ( just want to
confirm if it is phosphates crystal )
tq for the info anyway oreo..

i dont know what my water company use, but if i am not
wrong, my tap water basically come from a well.. not too sure.

The coconut does not have meat in it, i have also boiled the
coconut for around 7 hours before putting it in there..
well, there is no substrate =)
the background it made of straight cement + grout,thats all..
the tank is not a new one..
i used to keep some fishes before draining out the water
and fixed in the background..

well,
there is only background and coconut...
the water is pretty clear but abit yellowish, i dont know
if it is because of the light effect..

 

[mike dunagan]

Did you seal the background?

 

[davescube]

yes, i seal the background..

 

[Adam-011]

I had some of that on somthing in my tank about 3 weeks after it cycled. Not nearly that much but I had two Chinese Alge eaters. They took care of it in like two days.

 

[davescube]

if those thing are not actually harmful to fish or aquatic plant, i dont really mind..
for now, i put some fishes there for experiment
I hope they will be just fine

 

[killerfish]

looks like fungus

 

[davescube]

those thing is pretty difficult to be scraped off, i dont want to make more scratches
so i just leave it there, and i do 100% water change every 2 days, the condition is getting better now..
I assume pH is the cause of it like Orea mentioned previously..

 

[davescube]

I guess my pH should be around 10 right now...

My pH indicator reads from 6.0 to 7.6
pH of tapwater = 6.4
So here is what I get,
I use tapwater mix with tank water in the ratio of 5:1
and I get pH of 7.0

my own not so steady formula...

(7.0 - 6.4 ) = 0.6

0.6 x 5 = 3.0

so pH of tank water is 7.0 + 3.0 = 10


I hope someone would just understand what I mean, I am very poor in
describing..
And I really wonder If this way of measuing pH works

 

[dmed]

The pH really doesn't matter. Also, FWIW, the pH scale is logarithmic, so your calculation doesn't work. A pH of 10 is 1,000x more alkaline than a pH of 7. A pH of 10 is close to that of many household detergents (undiluted).

The "alkalinity" leaching out of the concrete, if this is happening, would be better measured as "hardness"

Get a GH and KH test kit. Test the tank water and the tap water separately for GH and KH and let us know what the results are.

 

[davescube]

I doubt I can get that test kit here...
I am so desperate to put my substrate, fishes, and plant in there..