Brown algae after cycle - OUT OF CONTROL

[Punchanello]

Hi all,

Two things have happened - 1. My cycle has finished and 2. My skimmer hasn't arrived!

I now have a mostly free floating powdery brown silt making the water murky (and a little smelly). Like...really murky. I assume it is diatoms(?).

I'm cleaning and changing the filter socks every morning and evening in an effort to filter it out but I assume most of it is just passing through because I haven't seen a reduction.

What can I do until my skimmer arrives (I assume that would help remove it from the water column?

Lights out?
Would activated carbon help?
Water changes?
All of the above?

Kind of concerned my water is become a bit rancid. Any help greatly appreciated.

FYI I am using RODI water. I have no fish or coral stock yet. Started cycle with dead live rock. No sand or gravel.

I should also add that I saw a film of the algae covering the glass and rocks. I blasted it with powerhead thinking it would end up in the filter sock. No I just have murky water.

 

[Drewbe147]

Big water change. I would probably 100% WC being you have no livestock yet. Dry rock curing can be quite nasty and smelly and literally make water brown. Most like to do this in a covered container like a brute trash can or whatever. Lights will promote algae growth and isn’t needing with no livestock so I would keep them off when not maintenancing the tank until you have livestock. Most likely by the sounds of it though is the rock curing is most likely your problem. 100% WC and wait to repeat if rock is still curing. Theres youtube vids on curing dry rock. Some make more mess than others. Pukani for instance is generally very very dirty. Thats my opinion on your problem. Goodluck

 

[Punchanello]

Big water change. I would probably 100% WC being you have no livestock yet. Dry rock curing can be quite nasty and smelly and literally make water brown. Most like to do this in a covered container like a brute trash can or whatever. Lights will promote algae growth and isn’t needing with no livestock so I would keep them off when not maintenancing the tank until you have livestock. Most likely by the sounds of it though is the rock curing is most likely your problem. 100% WC and wait to repeat if rock is still curing. Theres youtube vids on curing dry rock. Some make more mess than others. Pukani for instance is generally very very dirty. Thats my opinion on your problem. Goodluck

Thanks Drewbe. My nitrates were over 100 ppm while the tank was cycling and I assumed that was because the rock was curing. Then it dropped over the course of a week or so to zero so I assumed that was the cure done and cycle finished (nitrates, nitrites and ammonia undetectable). The brown algae went devil-spawn almost straight after that.

I'll definitely switch the lights off and start doing water changes this weekend. Anything else I can be doing?

 

[Drewbe147]

Im still new to the hobby myself but after your WC in a few days if the water is not cloudy and parameters are good then I would add some snails (variety like cerith/turbo/astrea/nassarius) to help get going on the algae and make sure theyre doing fine then in a week or 2 add your first fish if everything’s fine. On the CUC though I wouldnt go buy one of the “cleaner packs” due to that being waaaaaaay to many for a new tank. For instance in my tank i started with 3 hermits first for a week then added5 nass 2 cerith 2 astrea 1 turbo snails in my 90 gallon. I am about to add another 1-2 turbos 3 more ceriths 5 more nass snails in a few days. Basically what I’m getting at is add when/as you need them. If you get 100 snails or whatever theyll eat all your algae but then starve start to die and put more nutrients back into your tank and then repromote algae growth again. I am running carbon passively in my sump from BRS as well and started with dry rock as well and my water is very clear. Hope this helps

 

[Drewbe147]

As for the diatoms though the snails will help with that too but it reproduces quickly absorbing silicates in the water to grow. Once the silicates are gone it will start to die out and disappear. If your water change water has high silicates then youll fuel the diatoms more for a short time. On your RODI just make sure your getting 0TDS and if your still getting strong and long blooms after each WC I would look into adding another canister after your DI resin on your RODI unit and add a silicabuster chamber to help polish your water removing more silicates that could be passing through