Monte Carlo Melting, Turning White - Advice Appreciated


New Member
May 11, 2020
hello. I would really appreciate some help in diagnosing what issue is causing my Monte Carlo carpet to turn white and melt. My tank is approximately 2 months old. initially started as a dry start with tissue culture from bruce plant which weren't that great, then added potted from aquarium that were much better. dry start was about 6 weeks. then I flooded. the first three-four weeks were great and the carpet grew out almost completely. the tank finished cycling and ammonia was at 0. then suddenly the plants started turning white and melting within a matter of days. I thought it was due to low calcium and fluctuating co2 levels. due to the melt I had a huge algae issue which I resolved with excel. I dosed excel about two weeks ago. I was doing water changes every other day during excel dosing and now doing them twice a week. my carpet is finally growing back but today again I noticed some of the new growth turning white! This happens very fast in a matter of one day. I don't know what's going on at this point.

here are my tank parameters

Amazonia version II

60 gallon tank running on two oase bombaster 600 thermo

one has a uv sterilizer and the other co2 diffuser and reactor

I have twin star light set at 75% for 6.5 hours a day - afraid to go longer at this point due to dead plant material still dissolving from the initial melt and algae

co2 is yellow - this is accurate, used two different solutions and using kh and ph chart it all correlates - I have only a betta fish and he doesn't mind the high co2 level

I'm using green leaf aquarium ferts for EI dosing using the rotala butterfly calculator. I mix them in 500ml gla bottles.

also using green leaf GH booster

I have some crushed coral in the filter to raise the PH a little bit for when I'm ready to add fish.

I double dosed on the micro nutrients and the white spread seems to have stopped today.

GH 9

KH 5

Ph 6.4

Co2 38-60 no fish

Ammonia 0.25

Nitrites 0.25

Nitrates 40

please let me know your thoughts. much appreciated

monte carlo white.jpg

my aquarium.jpg


Super Moderator
Staff member
Lifetime Member
Jun 20, 2016
I would suggest that the ammonia is still leaching from the Amazonia. A cycled tank should deal with a few plants melting off, but it’s probably also dealing with the soil. The melting, once it starts in a leaf can spread to a new leaf or plant by direct contact. Probably a reaction to the decaying leaf nearby (either local conditions or abundant decomposing bacteria).
So try whenever possible to remove the leaves that start completely melting. With a carpeting plant obviously you can’t go individually but you can take a turkey baster and gently push pull water over the surface to detach damaged material. Also looks like it’s time for a surface vacuum cleaning. Keep up the twice a week water changes.
I would also reduce the light intensity to 50%. Turn off the UV, it messes with iron chelation.
My preference is to also remove that crushed coral from the filter, at least for the time being. You already have a KH of 5, no need for more buffering. You are adding lots of CO2 which create acidic conditions so you end up dissolving a lot more coral than in a normal fish tank.
Also aquasoil soaks up a lot of PO4 at first. I usually dose 0.5mg/L PO4 daily when starting out and still run out …tested it once and it took up 5mg/L PO4 overnight :)