shrinking mushrooms

[Ken]

I have mine under metal hadlides some in 400 watt, some in 175 watts, some in 250 watts, some on the upper tank sections some on the bottom sections and are thriving. In my tanks it seems like lighting is not really an issue, as some are also in my small 20 gallon with a single 24 watt powerglo. Check your iodine level perhaps. Regards.