Urgent help neded

[Morbillis]

Will tell the story how it was...


Tank is a 14g biocube with stock lights. Running for 3.5 month. Of course not everything was smooth, went through some dino problem which I managed with a blackout. But even then corals were doing great.

Have some zoas, hammer, candy cane.
Four weeks ago noticed increasing population of flatworms. I took a challenge and dosed tank with flat worm exit. Had to treat several times. Once with double dose. Of course I followed the manual, partial water change and carbon. But things seemed gloomy then before. Snails sitting closed and never went out but did not die, cause they react on the touch when out of water.

I thought it's temporary and eventually things will bounce back. Two weeks after I got myself one Devils finger, plate coral and some lps from a frag swap. But things keep on declining. Now it's three weeks period and system is crushing, some corals show skeleton in last few days.
Water parameters are:
Nitrate 0
Phosphate 0.25
Alk 8
Calcium 380
Ph is low, 7.5-7.8 but it was always this low for some reason since the begining.

It's a fish less system, no major algae break observed, small refugium on the back for the last two weeks or so.
I feel everything is doomed and I really need some support here. Any ideas fellows? Help me to save my reef,,,

[bertoni]

That phosphate level is very high, if accurate. Are you adding any food to the system? I'd probably start with some water changes and add a GFO reactor to the system.

[Morbillis]

thank you, will try!

[bertoni]

You're welcome! Please let us know how well GFO works for you.

[dkeller_nc]

Given that you have a 14g tank, my first thought would be a series of water changes, because that's very easy with such a small water volume.

There's no reason not to put a small reactor in with GFO/GAC for the longer term as it may help you manage nutrient export. But for the short term water changes will help you get the phosphate under control much more rapidly and at much less cost than GFO.

The only thing I'd caution is that with such a small water volume, you may want to be cautious about the condition of the change water - i.e., that's it's at the correct temperature, specific gravity and an alkalinity that approximates where you want the tank to be.

Many folks with nano tanks do nearly 100% water changes, but as noted, they're very, very careful about the change water.

By the way - a pH of 7.5 - 7.8 is unusual, and is worth investigating. If you're using a properly calibrated pH meter to measure this, I'd look into whether you're getting enough gas exchange; a build-up of CO2 would cause a low pH, and if that's being caused by poor water movement, a malfunctioning skimmer, etc..., it's also possible that the oxygen content of your water is low.