What is this?

hey,

So I have been cycling my new 200 litre tank for only 2 days now and last night I spotted this weird white stuff across the substrate. Can anyone tell me what this is, if it’s harmful and if this is normal?

Thanks in advance

Photo is not clear, but it seems to be a fungus. If it is off-white, probably fungal; if more green, possibly algae. Algae is harmless as such, fungus depends. I assume you are adding a source of ammonia...what exactly?

It is white and I haven’t added anything to the water at all, the only thing in the tank is declonrinated tap water and the substrate

When you say the picture is not clear, the blurry stuff is the white/clear stuff I am talking about I have no idea what it is

If you haven't added ammonia you haven't been cycling the tank, just letting it run.

You have 2 choices.

You have posted about plants; if you have enough of them - more than just 2 or 3 in 200 litres - you need to make sure they are all growing well, then add fish a few at a time. Check for ammonia and nitrite daily for several days after each batch of fish and only get the next batch if these levels stay at zero. Plants use ammonia as fertiliser, and if there are enough of them and they are actively growing, they tank up all the ammonia made by the fish. The floating plants you asked about in another thread are particularly good for this.

The alternative is to keep the plants in a separate container and do a fishless cycle by following this method http://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/ Plants do not do well when ammonia is added in a large dose as in fishless cycling, so they should only be added to the tank after the cycle has finished.

Oh okay, sorry I was just confused as this is my first time keeping fish.. I now understand the process. As for adding fish I have 2 guppies I can add if this is suitable to start with, as for plants I only have 2 Cryptocoryne wendtii but I can get more plants tomorrow. Thanks for your help

Back to that white fluffy substance, it is likely some type of fungus. I asked if anything had been added because fungus appears on objects when organics are present, such as some pieces of wood, and fish food left uneaten. There may be some dirt or something in the gravel...assuming this is normal gravel; or is it an enriched plant substrate gravel?

It’s just normal gravel I bought for my local fish shop, should I manually removed this fungus then?

I bought some rocks too which are also in the tank so it could have come from there.

It had to come from something, which could be the rock, gravel, or I the source water. Or I suppose in the air. If it will come out with a Python during a water change, might be worth doing.

It like the stuff that grows mushrooms, it's everywhere

Mycelium

filamentous diatoms they are called...

After putting in a couple guppies to start the cycle they ended up eating this stuff, I also added some frogbit to the top and the crypto wendtii in hopes my guppies will survive the cycle. Can anyone recommend how much and how often to for a water change? It’s 200 litres. Thanks

LunarisSurge said:

After putting in a couple guppies to start the cycle they ended up eating this stuff, I also added some frogbit to the top and the crypto wendtii in hopes my guppies will survive the cycle. Can anyone recommend how much and how often to for a water change? It’s 200 litres. Thanks

Click to expand...

You need to test ammonia and nitrite daily, preferably in the early morning (after the tank lights have been on for 30 minutes or so is a good time as it is consistent). If either are above zero, a water change of at least half, preferably more, should be immediately done. This continues until ammonia and nitrite read zero consistently.

This might not be problematic, depending upon the tank size. Two small guppies in say a 20g tank is no where near as problematic as half a dozen larger fish in a much smaller tank. You also have some plants, even if not fast growers, which helps.

Once this is passed, water changes should be regular (no les than once a week, on the same day) and substantial (half the tank volume). Absolutely nothing beats partial water changes.