A good sealant?

[Aikidoka]

Ok guys, thanks for the input, appreciated it! I have another question, will you use the old bio balls that's been sitting around for years?

I know it's better to use LR vs BIOBALLS, is it still effective? Will it still do the same job? Lets just set aside LR for now, if only our option is bioballs, will you use it? Or buy a new ones?